I'm 20 years old and have been trying to research what maybe causing the pain I experience in the tip of my penis, I'm leaning towards it being Peyronies disease and wanted a medical opinion on it.
About 7-8 months ago I started to experience a shooting pain in the tip of my penis about a cm in or so at most, and on the bottom side. At first the pain would come and go randomly, either during sexual intercourse, prior to it, during masturbation and erections or just on it's own. I also experienced pain while urinating in the first few months. I did not want to go to a doctor but feared it was an STD from unproctected sex, though when I finally went to seek help the pain started to dissipate and happen less, it's about 3-4 months from when it was at it's worst and and 7-8 total and now the pain just comes when I'm in the process of an erection or at the end of climaxing where I feel short sharp pains at the end of an orgasm in the tip of my penis. The reason I'm hoping and leaning towards this not being an STD is the pain like I said has lessened not to mention ceased during urination for the most part and only happens during an erection or the end of climaxing mainly, though occasionaly it will randomly be felt.
What also lead me to believing I may have this disease is that sometimes when urinating it almost feels like a blockage, or something that has lessened the diameter of my urethra near the tip of the penis, especially after sex.
Am I looking at an STD, Peyronies, or something more serious here?

It is certainly not Peyronies, which causes curvature of the penis. If you have had unprotected sex, you cannot rule out an STD. Even if the symptoms go away, you could still have it. It might not be an STD, it might be something like prostatitis, so you really should see a doctor about it. You have been in some degree of pain and anxiety for some months now, and all you may need to finally feel better is to see a doctor and take some pills. If you have untreated chlamydia, it might be slowly wreaking havoc internally to you, so please go see a doctor.