My 5speed Pontiac wave revs so high and I'm only going 25 miles per hour

Me neither.
I don’t believe the vehicle is safe on the road in this condition. It can’t keep up with traffic and it’s scheduled to stop going forward any moment now… and that can create a serious road hazard or leave you stuck in a place where you don’t want to be stuck.

Make that three who say “no”. If you can’t postpone the upcoming trip, or catch a ride with somebody else, either take public transport, or rent a car. You risk having a show stopper breakdown at any time if you continue to drive the vehicle. Might be worth the risk if you are drives a mile along neighborhood roads to the grocery store etc, but not any long trips, especially on roads requiring high speed to keep up w/traffic. If it is further than you’re willing to walk back home, don’t try it.

Schedule a visit to your mechanic so they can give it a look-see. Who knows, you might get lucky and there’s a simple fix. Unlikely, but such a thing is possible.