I am experiencing the same problems as you now that I have had surgery about 8months ago for an Inguinal hernia that I had. Both size and width seem to have changed and erections seem to be rare. Im only 21 so I'm a bit worried at such a young age. Ive heard from other people that they feel that it may be due to the mesh used that could be possibly blocking blood flow? But for any doctors or anyone with a lot of knowledge within this, my question is how do I get this problem fixed? Would I have to go through more surgery for it to be done? And, is the doctor at fault for this, or do these things "just happen" after some surgery's?
And also, for the pain part, I don't think you should worry about it a whole lot. I had the same exact pains for a month or so before they went away. Also it is normal for there to be pain during ejaculation, I had this and asked the doctor because I was worried, but it went away a few weeks after.