I Have A Swollen Bump Above My Left Ear. It

I have a swollen bump above my left ear. It all started as a tiny bead about 8-10 months back & was painless - so I ignored it. But it has been growing for the past about 2-3 weeks & pains slightly when pressed. My GP says it is a hairless cyst - however, she put me on antibiotics becoz I reported slight pain. However,after 2 days of antibiotics, there is no change- in fact the swelling has increased , and pain level is same ( slight when pressed). I don't know what to do & am worried. Plz help me.