when I was 11 weeks pregnant, i was given the 'ok' to take sudafed and it helped tremendously..
at the time i also was a really bad insomniac (well still am lol).. and was given ambien.. but now i can't remember if he said it was safe to take during the whole pregnancy or just the 1st tri or 2nd tri... cause i'm in my last trimester and i know there are some meds you can take early on but can't take later (like Motrin cause it closes the ductus arteriosis early)..
anywho, hope you feel better! you should try the preggy pops they help the nausea

but of course, always ask your ob because they know best... and all Ob doctors are different.. so just because 1 person says their doc can take this, doesn't mean your doc will say you can too