Series 4 Watch Slow Charging

I have a Series 4 Watch that has recently started to charge much slower. I know it is old but it meets my needs as I don't live on my electronics but the watch is my best friend due to irregular heart rhythm. I originally purchased the watch in 2019 but the stem went bad and they sent me a brand new watch head 6/2021, not a refurbished watch. I do carry Apple Care for my watch. I am teetering on buying a new watch vs. keeping my current. Do any of the community still have an older watch they use and can tell me if theirs charges slow? I am not a technical person so I fear I will not be able to learn the changes Apple made to the new watches. Will the apple store help me set up a new watch? Is there any data stored on my current watch that would need to be transferred to a new watch or would I have to reset all the data that is in my older watch? Thank you