hamsterz saidI don't think my diet has changed, but I probably could eat much healthier (like more fruit and vegetables). Could what i eat be a reason why my sperm has turned to a small watery amount?
A change like this should prompt a visit to a urologist. The reason may be entirely benign and of no concern, but likewise could indicate more serious issues. A PSA blood draw (prostate specific antigen) will be done, along with a prostate massage and palpitation of the testicles, possibly taking a slide sample of a urethral discharge if the prostate is "milked."
I've also been directed to masturbate into a vial in private (supplied with Playboy magazines that did me little good), for a sperm count and other evaluations of my semen. I'd expect them to also collect a urine specimen from you.
There are other tests they may do, as well, but probably not until they perform the ones I've mentioned above first. I do recommend you have this done soon, since changes like this to our bodies need to be properly evaluated. Thin semen in itself is not necessarily unhealthy, but the CHANGE warrants medical attention to determine the cause. It may be natural aging, or it may be a disease process. I encourage you to find out which from a urologist.