After 7 months you should have seen improvement. The pruning might have help it out - shock it into recovering.
Is it in the ground? Or in a pot? If it's in a pot: DON'T water it as much as you were; the plant isn't using as much water as it was before it was pruned, when it had lots of leaves. Hibiscus hate wet feet, which is when the soil stays wet around the roots.
It's going to take a while for the plant to recover. Just be patient; it's probably going to be late March before it shows significant improvement.
Good luck! Even if the plant doesn't recover or takes a long time to do so, it's a great learning experience.
Barb