Did you ever figure out what it was? I have been having the exact same problem. My throat had been sore and the gland in my neck are swollen, But i have no other symptoms. Its been going on for a total of two weeks now, but for about a day or two it went away, then came back. Im very worried and would like to know what it is.
Symptoms of an oral STD do not show that often and if they do they do not show 1 days after the event. This is not going to be STD related.