I decided not to put her in a breeding tank and to let her be until she shows symptoms. she has not shown any symptoms yet except that she has a big spot in the back of the tank that she likes to keep to herself. Is this a symptom? i have never had a pregnant livebearer do that. normally they hide in the corners.
Yes, it can be. Or she could just be resting, trying to stay away from the male.
How big is the breeder tank? If it's at least 5 gallons, and has some plants and decorations, she shoould be fine in there until she gives birth. It's the smaller nets and traps that you can't keep them in for long.