Yeah, two things I'd check...
How tight are you making your boots? You shouldn't need to crank them, just snug should be fine otherwise you might start cutting off circulation... That brings me to point #2.
For point #1 to be possible, your boots have to fit right. Most people buy boots to big to start. They expect them to be super comfortable right off the bat. They should actually fit more like skates at the start. Your toes should just barely graze the end when standing up straight, and your feet shouldn't really have room to move. After a couple days the liner will pack out and you'll have a good fitting boot.
What usually happens is people buy something that fits in the store, and within a couple runs/days it packs too much and gets sloppy, then they have to crank their boots too tight which gives them really sore feet and still doesn't fix the boot fit issues.
The other thing is, you do use a lot of foot muscles when boarding, like Donutz said it just might take some getting used to!?!