Is my transmission a complete loss?

What is your question?

The other day I got on the freeway and it began reving to really high rpms and not engaging. We checked the transmission fluid and none was registering on dip stick. We have now out 7 and a half quartz into it as the manual says it should have and it appears to be at the proper level. It will go into all gears and drive however only for a short period of time. Then it won't kick into any of the gears at all. It appeared to be leaking fluid after we filled it up but that may be overflow or something. The check engine light goes off and on sometimes but had been on for a couple days prior to the transmission problem. Is there any chance the entire transmission does not need replaced?