1994 Mazda MX6 Engine idles too fast

Heyyy, I just like to say thanks for taking the time to answer questions on this site, when everyone knows, you guys could be doing other things more important but you choose to do what you do.

Moving on.
I recently got a tune-up cause my car was really in need of one. Everything was running nicely but I've noticed that the longer I drive now, the faster my engine will idle. Like. After 20-30 minutes of driving, the engine idle will be running around 1100-1300rpm say if was stopped at a red light. It gets to the point where I have to use a lot of pressure just to hold my brakes from stopping me from pulling forward. When the light goes green, I can reach roughly 40km/h without even accelerating.
I'll also notice that when I put my car into park, it will rev up to 2500 rpm. At times it will idle so high that the little needle will bounce up and down repeatedly like it will go up around 2600rpm and drop down to 1100 and then go back up again in a quarter of a second. I know this isnt normal. My car is slowly getting to be a discomfort when drivng. What could be the problem?

Thanks for any help!