no , one has answered, so, sounds like your USB port is bad. its not terribly uncommon for this phone, if stress is put on that port. not terribly hard to fix, but need solider skills etc.
the power button, i dont know, you could find out once you go to fix your usb port. replace that too.
lastly, sounds like the USB port is just gone now since it wont turn on ? it wont charge? i'm not clear on that, so, try finding another way to charge the battery and see if the phone works or powers on again.
these phones do get warm, when doing navigation with GPS on, while playing music etc.....
seems like based on your description, like its not " dead" as it has started once, after crashing per your description above,
hope this info provides some help for your issues, I would be more specific , i only have so much info and with the info I provided here, should be able to diagnose it further and fix it, or provide more info as your testing progresses.