You had a pimple on your penis for years? I don't think that's a pimple. A pimple wouldn't be there for years.
Kissing doesn't transmit anything - you're fine there. No risk.
From receiving oral sex, you are at risk for gonorrhea, chlamydia, NGU, syphilis, and genital herpes type 1 (if you don't have oral herpes type 1 already).
You can test for gonorrhea, chlamydia and NGU at 5 days. This is a urine test.
You can test for syphilis at 6 weeks. Syphilis is uncommon in most developed countries.
If you don't already have oral herpes type 1, you can test for herpes type 1 with a type specific hsv IgG at 12 weeks.
You are not at risk for HIV.
The chances of you getting anything are much lower with oral sex than with intercourse. Most experts don't think one act of oral sex warrants testing.