I’ve seen this before in cars… a lot… damn gm’s… good thing i know what i’m doing under the hood. sounds a lot like your alternator is dead. Any mechanic/Autozone should be able to test it. If you don’t feel like taking it somewhere, charge your battery, start it, let it idle. then once it dies check the voltage across the battery, if your battery is dead, it’s your alternator. If it’s still got life then you’re going to need to take it to a mechanic, and they’ll check your carb’s jets, run some carb cleaner through it, change all the fluids, etc. until they find the problem. unfortunately this could get expensive. Then again, if it was cold during your ride, and you weren’t riding in high enough RPM’s, your engine could just be cooling to much and seizing, Ive seen that all over the small engines i’ve worked with. Remember to be genorouse with the choke on those cold starts, and take your time warming it up. It’ll save you a lot of heartache later, believe me. Good luck
ps. Please report back.