38 Weeks 1 day pregnant!

So today I started doing my baby's wardrobe and sorting out clothes into sizes, took me 3 hours and when I had finished I had a sore back was feeling dizzy and a little shaky. When I got chips and curry I had to open my window to get fresh air and I was ok after that ever since then I have been getting alot of pressure, Cramping and pain around my belly and vaginal area. I can barely move when it happens when I was lying down my whole belly was rock solid I know it may sound like Braxton Hicks but is it that? This is like the 4th time it's happened since 8.30pm it's now 1.31am and I still feel pain while the baby is moving.

Any ideas what this is as I know it's not labour as I haven't lost my mucus plug or leaked.