2007 Ford Edge over heating

What is your question?

So my check engine light came on. Then the next day it was off and stayed off fow awhile then came back on. To it to the part store to have them read the codes. Said something about the theromsat. We just put a theromsat on it in late June 2018. They reset it and it stayed off for a few days. Then one day I noticed it was getting hot so I pulled over and shut it off. Waited a few minutes turn the heater on and drove it a few blocked to a friends house. It had started to cool back down then. Let it set for a little bit then popped the hood up there was nothing in the reservoir and everything seemed to be wet. My friend filled it up with water and it was fine. Like 2 weeks went by no problems. We traveled from South Texas to Kansas and getting ready to come home the light came on and it started over heating again. I pull over shut it off and waited a few turned the heater on and drove it to the nearest store and bought some antifreeze cuz it was empty again. Then again 2 days later.

What makes this problem better or worse?

Takes a little longer to get to normal temp. Then jumps to hot

How long has your 2007 Ford Edge had this problem?

About a month