Taking this for a sinus infection that wont go away. Waiting for ...

Taking this for a sinus infection that wont go away. Waiting for results of cat scan. I have already tried taking Augmentim 3 times didn't work so not doxycline. The first 2 days was awful stomach issues. Burning in my stomach. The paper said take on empty stomach unless you cant take it so I started taking it right after my meal and much better. The nausea and burning and vomitting feeling went away after 3 days. So did the heartburn. But now I am EXTREME dizzy. While driving I feel out of it and tired and when I get home I start feeling the room spin and freak out so I lay down and then I am done for the night because I am just so dizzy and off balance. Today I got dressed for work and I was going to put on some higher shoes and couldn't balance myself so I stuck to flats. I only have 4 more days of this so I think I may stick it out. I just hope the dizziness goes away.