thanx for sharing your concern,
it is nice to know that you are taking adequate care of your teeth and maintaining very good oral hygiene
, whenever a patient is undergoing any orthodontic treatment, it becomes mandatory for him to maintain, a good oral hygiene, only then, your gums along with periodontal tissues will support in timely and proper tooth movement.
you have mentioned that after scaling you found your teeth loose and gums pulling away.
don't worry this is absolutely normal, after scaling this will subside in a day or two .
the bleeding from your gums will also be negligible in few days.
scaling is done to remove calculus and stains from your teeth , once it is done you feel lighter and some loosening and gaps in teeth . but don't worry those empty inter dental spaces were earlier filled with undesired CALCULUS and STAINS.
due to orthodontic tooth movement your dental tissues have moved a little in desired direction so do not be worried at all. just continue maintaining good oral hygiene and everything will be fine with this.