Apple watch won't turn on or charge

Apple watch series 3 (i think) won't turn on or charge. When I place it on the charger the apple logo comes on and goes off. When I try to hard reset while on the charger a red circle with exclamation point shows and tells me to go to apple support online. Not sure what to do from there. It looks like I may have to take a day and go to the apple store, but I was hoping there may be an answer here. I do not have the original charging cord.