I don't feel well and i hav a big dance in 3 hours!!!!?

last nigh i had a fever, but it was gone this morning, i didnt take my temperature, but am pretty sure that during the day i had a fever again. I have a big dance to go to in 4 hrs and i am congested in my head and chest. i can't be sick for this!!! do you have any ideas on what i could??? please help me out- i did take advil and it helped a bit.