They could give you a ticket. They might also bring out portables or send you back through. Both of which wastes your time. I don't know if you will get a ding on your license.
You are better off going in. Usually for most weigh stations it doesn't take that much time.
Doesnt make sense trying to run it. If you already blew by one by accident then you probably got away with it.
Of course these days i wouldnt be surprised if a camera isnt tracking trucks that blow by. Hadnt heard of it yet though.