most times U can not tell if she is pg or not. African cichlids as far as I can tell, do not get fatter but they do look heavy in the gut region when they are full of eggs.
Bloat now is she wil be really big in the gut region, and hide all the time at the bottom and NOT eat. bad if this is what she has. not curable if left to long..
U need a male of her species to see if she wil spawn with him.
HOW many eggs spots are on the bottom lower fin? (under the tail?) if lots, then it is a male, if one to parchal one, then a female depending on the species..
DO U know what it is?? Blue, red, white, striped, NOT striped and color of body?? I an help U here figure it out.. U can do a picture too.. Use the flash sideways into the tank glass to reflect the flash.. U do not have to be reall close to them to get a good pic..
Also food can make them fatter than they need to be. NO food for one day a week helps here.. KEEP The food protien down to UNDER 38%. Feed veggie flakes daily to all Mbuna cichlids as they more algae grazers which helps them move more food throught their digestive system.
Feed them a ZUCCINI sliced lenght wise ( or half that depending on how many u have in the tank) and achor it with a rock/rubber band or do a fork stabed in it to keep it down.. REMOVE it thought before it falls apart. LEAVE on the skin.. Do not add in other foods with it.. I just do a raw one and they eat it just fine. DO NOT USE A CUCUMBER AS it is different and they wil not be able to digest the seeds.
IF U can post a pic that would help a lot. IF Not then the color to stipes would help too help ID it.