I'll try to help, one question at a time. But the bottom line is that you almost certainly do not have HIV and herpes seems unlikely.
1) They may or may not have tested your partner for HIV at the time of his surgery, but people who have HIV rarely lie outright if asked. If he says he doesn't have HIV, you probably can rely on it. Anyway, if he isn't from an HIV endemic geographic area (e.g., subsaharan Africa) and isn't gay or an injection drug user, the chance he has HIV is exceedingly low. But of course you are in a much better position than I am to judge his truthfulness. But since you're nervous about HIV, you might as well be tested for it. As I have said many times on this forum, all the verbal reassurance in the world may be less helpful than having a negative test result.
2) Your description doesn't sound classical for herpes--but herpes usually isn't all that classical (even herpes experts often cannot reliably tell just by looking at a lesion). On the other hand, it doesn't sound like HPV either. The way to know about herpes is to have a blood test to check for HSV-2 infection.
3) Your symptoms could be any of a number of things, all much more common than HIV: bad cold, influenze, mononucleosis, and others. Or, concievably, herpes. See above re HSV testing.
Finally, while you're at it, get tested for other common STDs, especially gonorrhea, chlamydia, and syphilis. I don't particularly suspect them, but they should be done routinely at least once a year in young, sexually active people; and this would be a good time.
Good luck-- HHH, MD