Am I sick?

I have tons of nasal drainage. By head was hurting from 3:00pm - 2:00am yesterday. I spent the ight at my friends house last night and fell asleep at around 3:30 and woke up at about 8:30. I ate two doughnuts for breakfeast and felt fine except for the nasal drainage irritating my throat. Then when my dad came to pick me up I felt rlly tired while in the car and then felt rlly nauseus ever since. We got mcdonalds at noon and I haven't touched it cuz I'm afraid I'll be sick (im a total emetophobe) when I came up stairs I took my temp and it said 99.4 I immediately took it again and it said 99.1 and then 98.8 and everytime I take it now it says somewhere between 98.5-98.8. I do get seasonal allergies but I can't tell if this is all allergies or if I have a low grade fever and am sick