My ear bothers me. What's wrong with my ear? How can I fix it.?

I was sick for about 1 month with a slight case of bronchitis. Around Halloween I went to bed, woke up and my ear was bothering me. Not painful, but like I couldn't hear in it well at all. All the sounds in that ear were muffled. I saw a doctor and he prescribed me antibiotics, which I finished about 1 week ago and said I did not have an ear infection. Now today my throat is still a little sore and when i have my head upright like normal, my right ear feels plugged/blocked, but when i tilt my head to the right and downward, it opens up and i can hear normal. then it gets "blocked" when i putmy head upright again. its so annoying. what is the cause and how to i "unblock" my ear?