Did it seem to be overheating?
Blown head gasket? cracked head?
How does the coolant look? How about the oil?
No overheating. The temp was a little past the middle mark.
The coolant was low when it happened. There was only a small bit left in the reserve tank. I went ahead and put some in the radiator and the reserve tank. In all, I probably only put about 3/4 of a gallon. There's a little gunk in the coolant's reserve tank, but not too much. The coolant itself looks ok. It's a little darker than it was when I put it in.
As for the oil, it looks fine. No difference noticed in either the color or the thickness.
Also, it has been 2 days since this happened and I don't see any leaks on the engine or on the ground.
The engine struggles a little when it's started cold, but once it's warm, it runs fine. The only problem is the lack of acceleration. When I hit the accelerator, the engine sounds normal.
I almost forgot to mention this. The A/C was not on at the time.
I hope this information helps narrow it down a bit. I really hope it's not the head gasket and I don't think I cracked it.