Nausea at bedtime??

Hi Everyone,  Each night I sit on my bed to get ready for bed then get back off the bed to finish up and get into bed but for the past three nights when I stand back up before getting into bed I have a terrible nauseous feeling that makes me lie down right away and lasts for about 5 mins.  I don't know if this is related to surgery or just something that is happening now.  I don't have high blood pressure so no medication there and I have a snack each night around 9pm.  I am 11 weeks post op from RNY.  I have my 3 month check in tomorrow but thought if anyone else had this happen I could go prepared to ask specifically about it.  Thanks

Maybe its low blood pressure?  This started happening to me when I would get up too quick from a sitting position.  I was on blood pressure medication, and had to reduce it.  Or could it be low blood sugar?  I suffered from low blood sugar the first few months after surgery, and my clinic advised me to add a little more protein to my meals.  Is your snack protein forward?  Definitely mention it at your check up tomorrow.  Good luck.