low battery indicator light stays on

[ecuke]

After a long winter, I needed to charge my dead battery which was replaced 2 years ago. The battery charged in full in 5 hours. Drove for a few miles; went out the next day for a few miles, and then the light came on. Then shut the car off for 20 minutes and engine would not turn over. Then 1 hour later engine turned over but was weak. I have read some threads that this may be a regulator/alternator. Would another charge do the trick???