Sexual Problem. About my situation.

So I am a 19year old male. I suffered from injury to the testicle around two years ago. I got it checked out and everything turned out to be normal and I got a regular ultrasound aswell. But things didn't feel hundred percent normal but I thought with time it might change but till date I have noticed a lot of changes. Firstly I have completely stop getting morning boners like a normal male of my age would , secondly I notice the left testicle is abnormally smaller than the right testicle. Third thing is the lower left side of my penis hurts and I have had issues with maintaining erections. I cannot get erect without physically touching myself which was not the case before. The left side of my penis hurts sometimes also when I examine or move my left testicle a lot my left leg hurts a bit too. These are not just things made up by my mind. I have examined these stuff carefully. Please help I am really worried about my situation.