After replacing the thermostat when idling the engine shakes?

Hello and thank you for your time. Okay, so my truck was overheating for quite a while. I don’t drive it much, but when I do, it’s usually for several hours on the highway. It’s getting hotter in Texas and my last trip from Austin to Dallas, I drove most of the way with my heater full blast in order to keep my truck temperature down. I bought a thermostat and I put it in myself. Then started her up to get the fluids going and stuff. But now the engine is shaking something fierce! When idle, once I punch the gas, she runs and sounds normal. It doesn’t quite sound like it’s going to shut off. It definitely was not happening when I drove it yesterday. And I’m the only one that worked on the truck, so I know exactly what I touched and what I didn’t touch. I’m wondering if maybe some of the antifreeze got on some of the sensors and it’s making it freak out? Any help is greatly appreciated. Thank you for your time.