Vomiting at 34 weeks pregnant

I don't normally post but I'm getting concerned. Starting Sunday I've had bouts of nausea, vomiting, and mild cramping and it looks like baby started dropping. Last night before bed I threw up twice with a headache. And now today I've thrown up twice and I'm completely drained. I just had my blood pressure checked on Thurs and it was normal. I have never had high blood pressure and I didn't have morning sickness in the first trimester. I still feel my baby moving actively so I think he's ok. Has anyone ever struggled with this? Is it a sign of preterm labor?