What to do when a mosquito bite my eyelid and now swollen all around the eye?

I got bitten by a mosquito outside my door last night and my finger as I was trying to open the door. I didn't notice the swelling until I was ready for bed. It didn't itch except my finger. I didn't take an antihistamine last night because I had a beer after dinner. When I woke up this morning, my eyelid is swollen like an eye, can't differentiate the lines and moving towards the bottom of my eye. I took one antihistamine so far and nothing happens yet. Still very swollen.