You are having an upper respiratory tract
infection which presently could be handled by an appropriate antibiotics and antihistamine or corticosteroid. The rash you could apply topical steroid
but it is preferable that you get the rash examined by your doctor or a dermatologist
to give appropriate treatment. As for the positional vertigo, i will suggest you consult with an ENT specialist
for cause ( could be ear infection, nasal infection or other brain condition which could predispose to vertigo). In any case a specialist will be a of help.
Hope this helps you