Sinus problems

I have had a stuffy nose...lots of sneezing and blowing. When I sneeze the snot flies out of my nose. I have also had itchy ears and back of throat/back of roof of mouth. I also have some blood when I blow my nose.
This has been going on for a month. I went to the doctor after week 1. She said it may be allergies(I have never had any) and the start of a sinus infection. Gave me antibiotics and told me to take claritin and flonase. Nothing is helping and it is as bad as ever. I have tried every kind of allergy/sinus meds. Flonase makes me jittery and does nothing to help. I have done the neti pot for a week. Also getting blood when I blow my nose. Any suggestions? I have an appointment with an allergist in 2 weeks(for testing) but I can't go on like this. It is really ruining my life and I am scared it may be something really bad.