Should I care too much about battery cycles? I bought a MacBook Pro 13 inch 2017 two days ago and it’s been already 4 cycles 

Is it something that I have to care about?
It may have been through a handful of cycles in the factory for testing (unless you checked that it was at zero cycles when you unboxed it?). I'd just keep an eye on it over the next couple of weeks and make sure the number doesn't keep increasing too fast.