abs and brake light

[kellig]

hi, i would be new so excuse me if i'm doing this wrong. Anyways i have this problem with my 99' Pontiac Sunfire. The other day I'm driving and I stop at a stop light and my brakes jerk a little. My ABS and brake light goes on and my car won't move. It still runs it just wont move. So i put in park and restarted it. The lights went off and it was fine. I took it to a garage and the mechanic there couldn't figure out what was wrong. Only today I tried to start it before work and the same thing, it started, the abs, brake,battery, and check engine light went on, and again it wouldn't move. So I restarted it a couple times and it wouldn't move, the engine just revs. After i got home it started fine, no lights and its workin. Please help, what is going on