Troubleshooting engine damage after radiator hose failure

My mechanic replaced my radiator hoses. 2 weeks later, one came loose and the engine overheated and died. It was put back on and 2 weeks after that, the hose began to leak. I brought it back and both hoses were replaced, said to be faulty. An external compression test was performed but not internal compression test. What does that mean and should I take the car to another mechanic for further testing or monitor the car for a while first? It seems to rev higher upon acceleration, to 3RPMs but I have not had the car back for more than a day.