watch side button stuck
Watch will work, then if push side button it goes to screen as though it is being held. Turned off and now will not turn back on, just keeps resetting itself so apple logo is intermittently appearing and disappearing.
Try this:
How to clean your Apple Watch - Apple Support
Your best option may be to make an appointment at the Genius Bar in an Apple Store near you and let them look at it:
Genius Bar Reservation and Apple Support Options - Apple