Ear congestion? Help immediately-?

So I just got over an ear infection and I was prescribed amoxicillin for 10 days, 3 times a day. Did all of the doses. Got better. A few days later I got sinusitis and felt horrible. I got better, but I was congested. So then that was over and then I went back to the doctors because I was having cold symptoms which was just allergies. Took a few days to get over then I felt better. Just 2 days ago, I could feel something different about my hearing. While I am sick I know not to suck in all the mucus through my nose because that will go straight to your ears. So this whole time being sick I had to breath through my mouth which was annoying. I don't see how I could have ear congestion if I didn't breath through my nose. Please help, I can barely hear out of it. There is no pain or discomfort just it is REALLY muffled and I can hear myself talking AND my heartbeat which is really weird.