I typically will have my girls almost double in size when they go from veg into flower...Im going through height issues too
But mine r outside
U can check out different methods growers use to deal with height...I seen this on different site "growweedeasy.com"GOOD LUCK
Control Your Cannabis Grow Pattern with Bending
The last technique besides cutting your plant is to actually 'bend' it over so that parts of the plant are horizontal, and hold down the branches by tying them to something or using weights. Basically you're training the plant to grow the way you want, like a marijuana bonsai tree. By training the plant slowly and taking care not to hurt you plant (you don't want to pinch or snap any of the branches), you can get a plant that conforms to any shape that you want.
If I am growing two strains of marijuana, and one tends to be taller than the other, I'll bend over the taller one as much as 90 degrees so that it is the same height as the shorter plant. This allows a more even distribution of light and the the whole stem of the bend plant will get equal access to the light. Eventually all the buds on a bent branch will start growing upward toward the light. After initially bending your plant, growth will be slowed for few days as the plant recovers.
In addition, one of the natural reactions to being extremely bent over is the marijuana plant will stop trying to grow upward as much. As a result, all the lower branches will start getting more bushy. Bending your marijuana plants is a great way to maximize a small amount of vertical room.
This site has a great explanation for one way to bend/train your plant.
Cannabis Control Techniques Which Involve Cutting Your Plant
As far as methods that involve actually cutting the plant, you have two options. One is to 'top' the plant and one is to 'FIM' the plant. If you choose to use either of these methods, you will want to do it when the plant is young, usually when it has around 3-5 total nodes formed. Your plant will need some time spent recovering in the vegetative stage after cutting/topping/FIMing. You do not want to use any cutting method on your plant if it is in flowering (or is close to flowering) because it will cause too much stress for your marijuana plant when it should be focusing on making buds. If your plant is already too tall, you will instead want to try bending your plant to control its height, and try to change it to flowering as soon as it recovers from being bent.
Topping
Topping the plant means cutting of the marijuana plant at the stem under the newest node, directly above the leaves of the second node. So you cut off the stem right above it's second set of leaves from the top. This will cause your plant to transfer its energy to what is now the new top node. Your plant will react by making four main colas out of the new top node. The plant will also tend to grow bushier as a result and spread its energy around to the whole plant instead of just focusing on one main cola.
FIMing
FIM stands for "Fuck I Missed" referring to the fact that it's like topping your plant, only you're taking off less. FIMing is when you simply pinch off the newest growth, or cut just the tips of the newest growth off. This is much less traumatic to the plant and will still cause you to have four main nodes, but won't tend to cause your plant to get as bushy as if you actually topped it.
Here's a site with pictures that shows you exactly where to cut in order to FIM and top your plant.