They r near my south side windows - sorry typo

Also I have not repotted them yet

Why is it indoors?

Cos I live in condo and I wanna enjoy them better in my bedroom . However I will move them outdoor in my terrace in a couple months

Not much of a big deal where it is but I would be concerned about getting afternoon sun on a plant that prefers morning sun, dappled sun or even "bright" shade. Plastic pots that get direct sun may get very hot and cause "discomfort" to some roots.

Hydrangeas are not houseplants and do poorly in indoor conditions. I wouldn't delay too long in getting it outside..........it may not be in very good condition - or even alive - in a couple of months.

Ok thanks . Will repot them ASAP and move it outdoor right away if they don’t grow as much within a couple weeks

Consider it an annual or semi-annual plant if kept indoors in a low humidity area.

Consider them a cut flower if they are kept indoors. You could cut a couple of the blooms - near the top and put them in a bowl or shallow vase to enjoy in your bedroom. The sooner you move it the better the chance it will survive. If you have a shady spot - in the afternoon - you can just move it and repot later. I keep lots of hydrangeas in plastic pots - but keep them moist and water them if they seem to wilt. Make sure that the drainage holes in the bottom of the pot are not clogged or the paper wrapper is still on. Part shade to lots of shade is better than full sun - especially for a plant that was hot house grown or sold as a house plant.