Slightly deaf in one ear after cold?

I'm just getting over a cold, I still have a cough and sniffles. At first I thought my ears were just plugged from my cold. On Sunday my left ear started having pain from pressure, and now I can't hear out of my left ear. I can only hear very VERY loud noises. If I cover my right ear, it feels like I'm covering both. Is this just mucus build up from my cold? And will this go away soon? It's ONLY my left ear, and it hurts randomly.