headache and light headed post op day 5

Hey all, I had my surgery on Monday, am at home and getting plenty of rest.  But today I have a headache and my head feels both heavy and lightheaded at the same time.  Just a slight touch of nausea. 

The dizzyness is a bit concerning ot me.   I still have lots of gas pains, have been walking several times a day short distances.

I did a search above but couldn't find antying similar for so soon psot op.

Any suggestions? 

Are you getting as much water as possible? Could be dehydration.

I have had 3 8oz glasses of water so far today, plus I only came off of IV fluids yesterday.  Probably not dehydration yet.  

You know, I wouldn't discount dehydration.  I can't encourage you strongly enough to push those fluids.  Also, are you able to get any protein/calories in?  Sometimes I get light-headed from not eating.