Last night I was swimming in pool and my Apple Watch showed a thermometer, then that went away and I put on charger and it hasn’t been on since but it vibrated twice this morning and now nothing
Apple Watch SE, watchOS 9
Has it been a heated pool? Usually you will only get the temperature warning, if the Apple Watch gets too hot in your environment:
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copied from: Keep Apple Watch within acceptable operating temperatures - Apple Support
If the Apple Watch does not start on it's own again, you will have to get it serviced.
In that case have a look at your options on this Apple page:
Apple Watch Service & Repair - Apple Support
Has it been a heated pool? Usually you will only get the temperature warning, if the Apple Watch gets too hot in your environment:
...
...
copied from: Keep Apple Watch within acceptable operating temperatures - Apple Support
If the Apple Watch does not start on it's own again, you will have to get it serviced.
In that case have a look at your options on this Apple page:
Apple Watch Service & Repair - Apple Support
Your description suggests potential water ingress into the Apple Watch. Contact Apple Support and arrange to get it checked by Apple Service.
My Apple Watch went completely black and now the screen won’t show anything and it’s been on charger all night and I tried to force a restart
