I gave oral sex and two days later I've got a swollen throat like as if I have strep throat or tonsillitis how do you tell the difference I'm freaking out

Update

I went to a walk in centre I didn't have a temperature she believes it's an infection not tonsillitis. Asked me if I have anything going on down there which I don't so I answered no. She then gave me insulin prescription for 10 days. I wasn't tested for any stis so I assume after assessment it wasn't nessasery