So first - if you do have something, your life is not ruined. Second, chances are pretty low that you do.
From receiving oral sex, you could get gonorrhea, herpes type 1 (if you don't already have it), syphilis and NGU. The most likely of these is NGU, which is an infection in your urethra and can be caused by normal mouth bacteria entering the urethra.
Performing oral on a woman is even lower risk, and you'd be at risk for gonorrhea in your throat and syphilis. Chances of these from oral on a woman is slim, especially if the woman had no sores.
You can test for gonorrhea and NGU at 3-5 days.
You can test for herpes now to see if you already have type 1 - many do and most never get cold sores/oral outbreaks. If it's negative, you can test again at 4 months, but if you don't get symptoms, I wouldn't overly worry about this.
You can test for syphilis at 6 weeks, though it takes some people up to 3 months. If you don't get symptoms after 6 weeks, I wouldn't worry about it.
I read your thread in HIV, and agree that you aren't at risk for HIV from this. I know you are concerned that possibly intercourse happened that you aren't aware of, which would be highly unusual, but if you are concerned, test with the DUO test at 28 days. Remember though that if you remember the oral, you'd probably remember the intercourse.
Try not to freak. Most people aren't infected with an STD. Yes, this wouldn't be good for your relationship, most likely, but try not to catastrophize this. Guilt doesn't equal risk.
The left side of my lower stomach/groin, I believe it’s my inguinal lymph node has been getting more tender during the day and now has a burning sensation, does this change anything?
Your HIV questions were already answered in our HIV Prevention forum - https://www.medhelp.org/posts/HIV-Prevention/ARS-Recurrence-and-Timelines--/show/3044735
I totally agree with them, if that helps.
The only thing you can do now is wait. I'm surprised you haven't been vaccinated for hep B. There is a vaccine for that, and you should talk to your doctor about it.
I'd be very surprised if anything else comes back positive.