overtired and feeling sick

heya!! this is probably an obvious answer to this however, right now i’m so tired!

so my sleeping has been whack lately either sleep early or sleep way past 1am, and i love to sleep so it sucks, but sometimes when i want to sleep and can’t i just such tense headaches and feel sick! i’m guessing its due to over tiredness, but have anxiety when it comes to sicknesss! and freak out! any tips on how to stop feeling nauseous when being over tired? o and is it normal to feel headaches and sick when tired to?

Sorry for such a crazy explanation and question (just tired and feel blurgh )