I'm not sure about the side effects of the meds you are on but those symptoms sound like Vertigo. I'm not pregnant...(YET) but I had Vertigo about 2 months ago and what you described sounds very much like what I was going through. I would call the doctor just to have it checked out. Better to be safe than sorry. Best of luck to you!!!
I keep going into pre term labor also, and was in the hospital with mag. I was a little shakey when I came home,I did not get pain meds, so not sure about that but that was the only side effect I got, i would deffeintly call your doctor, best of luck to you
Jamie - since you're on magnesium sulfate, I would think some of this is coming from the drug - the pain meds definitely can cause dizziness & the falling/sinking feeling. But I really feel you should tell your doctor what's going on.
I know how you feel about needing to get some sleep - I'm sorry that you're especially not able to do so. I don't really have any ideas how to cure it since you're already on pain meds/antihistamine meds so talk to your doctor (wish I could do better) - jen