IME compressors usually have a thermal cutoff . If you do try to start them up too early, you'll know - it won't turn and the cutoff will kick in. Not great for your motor or premises wiring, but it has been designed for.

To the OP, don't regret doing this at all. Thermostats on air conditioners are generally subpar, since they're located on the unit itself. If you want to use the "auto fan" mode to keep noise down, then there ends up being large temperature swings. I think this is because the air stops circulating, while the air near the unit stays cool due to the cold coils.

I've got a plan to automate a dehumidifier Real Soon Now, and I'm planning on using a plug with current monitoring. This way I can sense when the compressor has shut off on its own and then wait several minutes for efficiency's sake.