What Causes Sore Throat And Difficulty In Swallowing Post Treatment For Salivary Gland Infection?

Hey there Doc, I seem to be having an issue, a few mounts ago I had what the doctor called a infected salivary gland. They put me on a round of antibiotics and made the hard gland go away but since then I have had a sore throat, minor discomfort when I swallow, comes and goes but has been this way for months thought it was post nasal drip but getting worried because I feel it at other times then when I wake up. I also have on the roof of my mouth (way back, can feel with toung) a bump small not painful but seemingly not symectric. Not really sure what s going on but would like an opinion. (All seems to be on the left side ) Thanks