So yesterday I was riding around town in my 03 cl type s. I stopped to get something to eat and left my car running while I ate. When I got ready to go my car acted like it wanted to die when I pushed in the clutch. Any ideas why?

Also, last week my car started to overheat when I was idling but cooled down when I took off. Luckily it was only my thermostat. I did notice this happened worse when my car got hot but yesterday it wasn't hot at all.

P.S: It wasn't extremely hot, just a little past half on the gauge. I is normally about 1/4 from the C.

 

Any ideas?? please