You can't tell anything from one day!! If I quit every med that made me sick after one day I wouldn't be on any, and I'd be even crazier than I already am.
I have been on Seroquel a couple of months and like it. But everything is different for everybody. Maybe you could check out the med reviews (under Ratings on the ribbon up top) here on PC to see if other folks have the same problems, or call your pharmacist. They're better at knowing drug interactions than drs. are.
If you were taking cold medicine (which usually makes people sleepy) and a sleep medicine at the same time, I suspect that would probably make you sleepy!, foggy, etc. No?