Only 3 days of laying is not a cause for concern yet. If it is a molt, then the feathers don't necessarily drop immediately, so she could be starting the process. It seems late for a molt though, as the winter is practically over. Also, sometimes hens literally take a break. I have a hen that occasionally stops laying eggs for a week or two at some point during the year for resting purposes. She is 2 years old and it has happened 2 times already. This is natural and not a problem.
Although the chicken looks healthy, you can certainly feel her to see if she is egg bound. Do this gently, as you do not want to break the egg. This condition is usually noticeable as the chicken will be walking like a penguin and not eating or drinking. I doubt this is the case, but you can still check if you want.
For micheleak, every hen is different. Some hens can hypothetically stop laying at any point of their lifetime due to genetics, reproductive issues, etc. One of my hens began laying eggs at 10 months of age. Was this unhealthy? Not at all, because she has always been in perfect health, but it is what her body decided. Maybe she will stop laying early as well? If that is the case, then I'm sure she'll continue to be healthy. Unfortunately when caring for chickens, very few things are set in stone with egglaying, and you just have to chalk whatever loose end you find yourself at as a loss. If a bird doesn't lay because she is egg-bound, then it is unhealthy, but a bird that just stops is ok, otherwise her body would not have allowed her to cease egg production in the first place. There are outside factors that influence a birds laying - like stress - and the hen will start laying again whenever she feels comfortable. You won't be able to put a timetable on that. Just do what you can to make your flock happy and you shouldn't experience many issues.
Hope this helps!
