3 day headache, nausa, and feeling really hungry after eating?

So today has been the 3rd day I've had a really bad head ache and the other 2 days i took Excedrin migraine and it worked but today it didn't and today I've been feeling really sick and have been hungry all day and I've been eating and it felt like i didn't eat. and i just stood up and felt kind of dizzy. and I've been drinking a lot of water but its been pretty hot lately but i have been making sure to drink a lot of water. and I don't know if this has anything to do with these symptoms but i know fer sure i'm not pregnant so i know that's not y i feel sick of hungry. well any answers will help and thank you for answering in advance.