Suggest Medication For Intense Pain In The Pelvic Area

I am a 25yo male. I have been having extremely intense pain in my pelvic area. I have had food sensitivity noticeably for a couple years primarily to gluten and dairy. The last couple months I have been getting a severe practically crippling pain in my testicles where they tube connecting them swells huge and is usually gone after a couple hours at most. Typically it happens when i ejaculate though what comes out is not much compared to normal and is very clear liquid and dont feel as if i have fully finished going also this happens on occasion when just like walking or laying down. I started to have very loose stool a couple months ago and now as of just over a week ago it is very firm. I am straining to defecate and urinate and is very painful. A couple weeks ago when this recent bout started I got a bunch of lumps in my rectum which at first I thought to be hemorrhoids until i realized how many there were and how far up inside my rectum they were and that it was all very inflamed. I received penicillin due to a possible syphilis exposure and something for a possible gonorrhea of the throat though have done 2 full std panels both negative for everything. The pain is very bad and often can not tell if it is kidneys, bladder or prostate. My appendix was removed after rupturing last year. I feel like i need to urinate and defecate constantly and when i can get anything to eliminate it takes extreme effort and time and just a slight amount produced never feeling much relief and when i do there is still pain down in that region. I have a difficult time leaving my place other than to reluctantly wlak my dog around the block as it is too uncomfortable and I am too afraid to go far from the restroom.