2013 Dodge Challenger miss shifting and overheating

My 2013 dodge challenger sxt was sitting in my barn for a month or 2 while I waited for a coolant line to arrive. well while the car was sitting a mouse ended up crawling into it and dying. Anyways I ended up getting the coolant hose and putting it on. drove to work no problem which is 35 miles away. Then I pick up my girlfriend and while leaving I got on it and it would not shift into second gear. I pulled into a parking lot and turned around got back on the road and it drove fine. drove down the road 3 miles and on the way back it wouldn't shift unless I let off the throttle, it did this about 3-4 times. Then I went to pull into her subdivision and my car was overheating out of no were. I pulled over turned it off and checked under the hood. No leaks anywhere pulled the dipstick and looked good; the tank was boiling hot. then it drove normal for the rest of the way home.