how long does it take to get dehydrated?

I posted earlier about kidney stones. I have not been able to drink much water today. its 2:45 right now and I have only had probably 4 oz of water that I probably threw up at some point. Do I wait until tomorrow before getting concerned or should I go to the doc? I feel a bit dizzy and I have a headache but I also have some pains from my stones and because I am about to start my period.

How long it takes varies.  If it's really hot or you are sweating, you'll get dehydrated faster.  If you're vomiting or having diarrhea, you'll get dehydrated faster.  If you weren't very well hydrated to start with, you'll get dehydrated faster.

Dizziness and headaches are symptoms of dehydration.  Are you able to keep water down now?  If so, you'll probably be fine.  But if you aren't able to drink now, then I'd give you doc's office a call.

You can also try the pinch test.  What you do is pinch the skin on the back of your hand.  Then let go and see if it goes right back to normal or if the skin stays pinched for a few seconds.  sometimes it's called "tenting" because the skin is kind of in the shape of a tent.  If you see tenting, you're dehydrated and need to go to the ER for IV fluids.

In addition to what Kelly said, unless you were already somewhat dehydrated, just being low on fluid intake for a single day is NOT a big deal.  The problem comes when it is a number of days in a row.  

Also, despite all the hype about it here on OH, not everyone needs 64 ounces of water every day to avoid dehydration.  I have gone almost an entire week after a couple of surgeries drinking less than half that amount and have not had a problem.  I know a number of people who don't drink much more than about 40 ounces on a regular basis and have never been dehydrated to the point of needing any kind of medical attention.

Lora

Oh my gosh, you poor thing.  You have a lot going on!  I hope you feel better soon!