the black spot people are talking about are the unborn babys inside the mother growing bigger, getting more colour and so we can "see" them inside their mother. with experience you will tell in future how long she has until she drops her fry if you pay attention now and remember what you see, which i think you are doing! instead of breeding traps i would get some thick feathery type plants like java moss so some of the fry can hide in.
finally try to relax and enjoy this what ever the outcome. they say fish keeping is relax full but i remember when my fish first had fry!!!!!!!