Very very VERY sore throat?

Okay so the past weeks for me have been very weird. First, I had a mild stomach flu. Then the week after, I had some very serious illness (still don't know what) that made me cough constantly and my bones hurt. i thought it was bronchitis at first. That was over in 4 days. Now, week three, my throat is beyond sore. It hurts so bad to swallow, and I can barely talk because it hurts so much. I have a runny nose, and as far as I know, no fever. Do you think all these sicknesses are related to each other? And what's wrong with my throat?