I'am 5 months pregnant with my 2nd child and for about a week now i have been experiencing severe nausea to where i feel weak and i had sharp pains in my stomach for a short period of time. Until now i havent had any symptoms with this pregnancy. The nausea usually hits around the evening. I dont know what could be the cause. I'am in a relationship and have been stressing. No medications. what should i do? Should i be worried?