My check engine light came on the other day. I continued to drive the truck for around 20 miles before arriving at my house. Once at my house I checked under the hood and found there was no coolant and there was a slight burnt smell to the engine. I refilled the coolant. There seems to be nothing apparently wrong with the engine but the check engine light is still on. I filled the coolant all the way up and after a few days the coolant level has dropped a bit. Is there a way to reset the check engine light? Could I have blown a head gasket?

Go to AutoZone and have them pull the codes for you. It sounds like something serious, but without knowing what the code/s is/are, it's just a guessing game.