I would check with your doctor just to be on the safe side, but I'm sure everything is fine. I used to get very hot towards the end of my 2nd, and into my 3rd trimester especially if I was moving around a lot, cleaning, etc. They sometimes say if you've been sitting for a while and then get up suddenly you may feel woozy.
Also make sure you are eating enough and drinking enough fluids so that your blood sugar doesn't drop too low.
I found some information for you, hope this helps: http://www.babycenter.com/refcap/pregna ... h/228.html