I’m not an expert but also have been very paranoid in the past just like yourself.
I spent countless nights researching and multiple anxiety episodes due to oral sex. I have taken many STD tests and all have came back negative.
I have been with many escorts and receive and performed oral sex on them and still nothing.
That being said any research I have done basically concludes receiving oral sex is basically 0 risk at all for HIV and small risks for other things but can be considered safe sex. You don’t have HIV.
If you can’t shake the anxiety go get tested about 4-6 weeks to be sure but 100% you are clean.
You had protected sex, and received unprotected oral sex.
As Jakekc said, your risk of HIV is zero.
If you got any STD from this (and your risk is very low), your symptoms would be genital, not oral, as you didn't perform oral sex.
Your symptoms could be from fighting a cold or the flu - it's that season.
The only things you'd be at risk for are gonorrhea, NGU, syphilis and genital herpes type 1 from the unprotected oral sex. The chances for all of them are low, as oral sex is lower risk than vaginal or anal sex.
Syphilis is only infectious if she had a sore in her mouth. It's fairly uncommon in most places, so I wouldn't worry about that at all, unless you get a round, painless sore on your penis. That can take between 10 and 90 days to appear, but the average is 21 days.
Gonorrhea is also less common, but you can test for that at 5 days. It's a urine or swab test.
NGU is any infection in the urethra that isn't gonorrhea. It can be caused by normal mouth bacteria entering the urethra, or even strep, or adenovirus (causes bronchitis and other upper respiratory infections). You can test for that at 5 days. Make sure they look for white blood cells in your urine.
You can get genital hsv1 if you don't already have oral hsv1 (think cold sores, though you can have oral hsv1 without ever having a cold sore). If your partner didn't have a sore on her mouth, chances are low that this happened.
So really, chances are low. No need to panic.