I don't know how to control my anxiety. Please help!

For the past week I've had chronic nausea caused by anxiety. It lasts from when I wake up till I fall asleep. The day I first started getting it I couldn't keep my food down but I can now. Today I had a panic attack. I'm not on medication I never have been. I just have no idea what's causing this terrible feeling because inside I'm so happy! I'm getting married to the love of my life and I'm 6 weeks pregnant. I just need some insight on how to control it. I wish I knew the cause but I don't. I've been through this before but never this bad and I don't want to harm my child. Someone please give me some sort of advise! I will greatly appreciate it xx