I sometimes take melatonin. I'm 39 and have been using it occaisionally for about 5 years. It works but I have really strange dreams. I don't think it would be a problem to use it in the way you describe. It's not addictive or anything like that.
You could also try benadryl (the allergy med). It has the same ingredient in it that the over the counter sleep aids have and it's also not addictive. I take it every night as I am allergic to almost everything in the world and have four cats.
Anyway I say it would be okay for you but I'm not a doctor and I don't play one on TV
Angela