Chance of Hiv

Ok here we go.
If you had unprotected sex, this puts you at some degree of risk. Since it was brief and no ejaculation occured, the risk is lowered but worthy of testing. But please remember, chances are very much in your favour that hiv was not transmitted in this episode.
Next, oral sex carries relatively low risk for transmission. There are not many confirmed cases but it is still a risk (albeit low). If semen is involved, the risk increases, since infection can occur from semen through the mouth (but not very often at all).
The symptoms you describe are, as with every other symptom which one may wish to attribute to hiv, unreliable for diagnosis. Yes, a sore throat can occur when the initial hiv infection takes place (during a time known as acute retro-viral syndrome or ars). You may also have a fever, headaches, nausea, night sweats, aching muscles and a rash. Or you may have none of these, or just some. There is no common set of defineable symptoms. You can see why symptoms are an unreliable means for diagnosis? Symptoms can mean anything - usually not hiv.
Ok, so remember that your sore throat could be just that. Everyone has sore throats. But- from what you describe, there is a certain amount of risk of transmission from your activities (chiefly the bried episode of unprotected sex) so you should get tested. Make sure that this is at least three months since your last unsafe sexual encounter for an accurate test result.
But please try not to worry, the chances that you are negative are very, very much in your favour, based on the physical risk, and the remote chance that the person had hiv in the first place.
Also, what you may think as being swollen nodes may not be what a doctor would define as swollen nodes. It is totally normal to be able to feel the lymph nodes in the groin - they are the easiest to feel.