10 seconds of oral sex is unlikely to result in an STD, but you are having symptoms, so you should get seen by a doctor and checked out.
It's also unusual to get symptoms 6 weeks later, but clearly, something is happening, and it's time to get it checked out. Let us know what happens.
Oral sex exposes you to syphilis, gonorrhea and herpes. You should test as follows :
-3 weeks after the encounter, for gonorrhea.
-6 weeks after the encounter, for syphilis.
-3 months after the encounter, for herpes.
The burning sensation could be because of the physical action of performing oral sex on you, as it can cause small lesions. Symptoms are rarely used to diagnose STDs as sometimes, they don't sow any symptoms at all. Just follow my advice regarding tests.
All the best.