Swelling on forehead/eye

Hello. I have a broad swelling above my right eye and the swelling is spreading to my eye. The swollen spot is not painful and there are acne pimple on and around the spot. I had a very similar situation almost a year ago, and different doctors offered different diagnoses, from cellulitis to an allergic reaction to a flea bite from my dog. I consulted a dermatologist yesterday  and he believes that the condition is acne-related. He prescribed me Tetracyclin and a topical ointment called Altabax. The swelling is spreading to my eye and I do not desire to have a puffed up eye like I had last year. Funnily, the spot of swelling is almost identical to the spot from last year. Pleae let me know if you have any ideas. P.S it might be useful to share that in the past weeks Ive attempted to "pop" the bump/pimple on my forehead, only to be mostly unsuccessful, although i have seen some discharge. Thanks again.