Serious question!!

I'm 12 weeks pregnant, and I randomly started feeling kinda hot, weak, shaky and dizzy all at the same time...it stopped for not even 10 minutes and now it's back again..when I stand up, it feels like I'm going to fall over. My pregnancy before this was ectopic, and the last time I felt really faint was when I was being rushed to the ER by my husband for the ectopic....help, just need to know if this is normal or what I need to do?