My hen, 5 months old, just laid her first egg and after laying she looks slow and inactive. She...

[Shady77]

 

[coach723]

Was the egg normal? Have you looked at her vent to see if it looks normal? New layers can have glitches, she may have another coming. It can sometimes take some time for their systems to get it all worked out. If she had trouble pushing it out it can make them feel bad, especially if the egg was large, rough, or soft shelled. I would examine her for anything obvious (make sure there is no prolapse), and if the egg was normal then keep an eye on her.