Why is my hibiscus (houseplant) so unhappy?

[Mia400000]

I was given this hibiscus and when I received it, it had dark green glossy leaves and beautiful flowers.

I placed it on my south facing window sill so it gets lots of sun and I keep it damp but not over watered.

The flowers were opening, closing overnight and then dropping off. Is that normal?

It now doesn't have any flowers and the leaves don't look as healthy.

Any advice?

laidbackgardener.blog/2017/01/13/the-secrets-to-growing-hibiscus-indoors/

It might have finished its flowering period and need to rest. Check out the site above for general infirmation.

Thank you. That link is very helpful.

I'm not experienced with plants and I fear this one is going to be tricky to look after ...