my guppy had 43 fry yesterday. when she had about 10 fry left to birth she started swimming on her side. i thought she was done though and i moved her to a 5 gallon tank by herself. she had 10 more fry but then she stayed on her side in the corner of the tank. she has a long white string hanging from her from giving birth. i thought she would be dead this morning and when i went to remove her (as there was no movement) she swam away.she continues to swim a bit then rest on her side at the top of the tank. what can i do for her

any idea what might be wrong

??