I'm kind of having the same problem. I'm 3 weeks late for af and I've used 3 HPTs which have all been BFN. I can't say I've had m/s though. Last night and this morning I was feeling a bit uneasy in my tummy but I'm not having it now.

I'm going to see my GP tomorrow to find out what is going on. I would definitely suggest that you see your GP asap especially considering that you can't keep your food down.