assistance

I need some assistance... I recently bought some aquarium plants, and with them came detritus worms (which I expected) but after a while, small flea looking bugs started swimming around my aquarium. There seem to be two different types as well. Some tend to glide around, while others dart super...

So I got some new fish recently, in particular a balloon belly molly and lyretail molly which, as you guys know, have live babies. Today I got home and looked in the aquarium and saw some strange things at the top I thought at first were bubbles, and then quickly realized were eight baby fish...