Mini fridge issue

I have a mini fridge which I put in my garage for drinks. Its worked like a charm for years, but needs to be defrosted every year or so. This week after seeing some ice buildup on freezer section (as I see every year) I unplugged it for a couple hours to defrost. When I plugged it back in the motor sounded very loud and would not cool. So I unplugged again for a few minutes, and now it will not do anything at all - thoughts? I hate to get a new one if this is an easy fix. It has worked with no issues for 3-4 years now. Thanks for your advice!