Answer: Your tree was probably going through an adjustment period adapting to the lower light levels and drier and warmer air indoors when you brought it in. Citrus also tend to drop a certain number of blooms just because they can't carry such a big crop of fruit. Indoor trees may not fruit very well if growing conditions aren't really good. Also, some varieties will fruit better indoors than others. Try to keep it in a very bright spot but on the cool side with higher humidity. You could prune it back a bit, but the legginess is also related to lack of light and possibly overfertilizing with nitrogen during the winter when it is not really growing much if at all. It may fill out a bit naturally next summer, too, when it is outside again. Also, if it is not on a dwarfing rootstock it may just be growing naturally. Here are some tips on growing container citrus you may find useful. YOu may need to cut and paste the complete url into your browser to make it work correctly.
I hope this helps!
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