First off, I would try taking the creatine ang glutamine at different times for a couple days to narrow down which you are having problems with for certain.
I find it to be very unlikely that it's the Glutamine, as Glutamine is now being used as a treatment for IBS (Irritable Bowel Syndrome) and Spastic Colitis. Glutamine as proved as effective and often more effective then prescription medications in the treatment of hyper-sensitive intestines. In simple terms it's much more likely to help your digestive system then upset it.
Next, your decision to stick with regular creatine monohydrate (creatine M.)is your biggest stumbling block. Regular creatine M. has the highest rate of intestinal upset of any of the creatine types available. More updated formulas have had to overcome those problems in order to sell product so the newer combinations are far less likely to cause the bloating, diarrhea and stomach upset that creatine M. does. For example the newer creatine formulations are often micronized. These formulations overcome solubility issues of regular creatine M. by using super miniaturized creatine particles. What this does is create a much higher bioavailability of the creatine which results in much faster absorbtion. So its absorbed with water in the small intestine very rapidly, instead of making it to the large intestine where it causes the problems.
I will make a couple different product suggestions for you, but before I do that let me tell that I have no financial relationship or benefit from any supplement I ever recommend. It's only on my experience and opinion for your benefit.
First, the best probable suggestion for you would be to use Kre-Alkalyn. Kre-Alkalyn is referred to as "buffered creatine", meaning that it doesn't convert into creatinine before reaching skeletal muscle tissue. Slowing or stopping the conversion of creatine to creatinine seems to help the body absorb more of the creatine, which reduces the amount needed and amount of it passed to the large intestine as waste. I know a lot of people that do not tolerate creatine well that do just fine on Kre-Alkalyn with complete elimination of digestive upset.
As far as saftey and effectiveness, its believed that Kre-Alkalyn has all the benefits of regular Creatine M. plus some additional benefit for some people because of less creatine waste in the digestive process. Kre-Alaklyn is believed to have the same strength gain, hypertrophy inducing abilities, and safety profile of regular creatine M.
Next suggestion would be to use a good quality product like Cell Tech's Hardcore Creatine. I don't recommend this product for the overblown marketing hype for which supplement companies are so well known for, but instead for a few additional benefits that it has. One it is micronized for more rapid absorbtion, reducing digestive discomfort. Two, the product contains BCAA's (branched chain amino acids)which help reduce catabolism (muscle breakdown) after a workout, they have been shown to reduce cortisol (a catabolic hormone) and increase post exercise testosterone. The BCAA's being substances required for life, are a natural way to improve the benefits of strength training and creatine. A lot of guys buy the BCAA's separately for different reasons, but this is a good way to get an additional resource in the same supplement. The Cell Tech Hardcore as well as some other brands also include the Glutamine in the formula which eliminates the need for yet another product, unless you want to take significantly higher amounts then are included.
Last if you question any of this advice I will offer you a cheap experiment. Go to any Walmart, and pick up a container of Six Star Advanced Pro Strength Creatine. Now before you have a fit that I've suggested something from Walmart let me explain. First I rarely recommend anything from Walmart but this is an exception. This experiment will cost you about 14 or 15 bucks for 2.5 lbs of it. This formula like the ones mentioned above reduces the chances of digestive upset, and does it in similar ways to the Cell Tech, plus some additional ways. First off, Six Star utilizes the biochemical traits of nitric oxide and insulin to increase the uptake of micronized creatine into the muscles. They do this in a pretty natural way by including several different forms of Amino Acids. CellTech actually uses a very similar method but instead chooses to tout their micronization process. Also where Six Star uses aminos to increase insulin, the CellTech uses a herbal mix. Each serving of Six Star will deliver 5 different forms of creatine in a 6 gram blend. They claim that the key ingredients in it have been proven in human clinical studies to be superior to regular creatine for building muscle and increasing strength. In any case, it is tolerated much better by most then regular creatine M. and at that price you can at least give it a try and see if it eliminates your problems. The fruit punch taste is decent for a creatine blend.
I know this got a bit long but I usually like to try to explain why I recommend the things I do so its not just another piece of generic forum opinion. That being said I should mention that all the information I've included is strictly based on my experience and opinions and is not medical advice.
I hope this helps bro. Good luck to you.