26 weeks and panicking

Danielle
So today marks my 26 weeks pregnant and I've only JUST started to panic about being pregnant. I was fine up until this point. I don't get it? 
When I first found out I was pregnant I had all the emotions (been trying for 2 years) but not once did I panic or get scared about it. 
I thought I would get scared and freaked out about being in labour and giving birth but right now I can't seem to get this fear out of me just for being pregnant? 
It started this morning. Woke up to pee, went back to bed and that's when it hit me. I felt the room closing in on me and I had to control my breathing. I woke my bf up and told him I was freaking out about being pregnant. His confused look and "but you're 6 months pregnant" reply made me laugh and calmed me..... until breakfast it happened again! 
Is this normal? I was enjoying being pregnant but now Im freaking out about being scared and I dont know why??