Judy Sanchez, of Fitchburg, says she awoke to heavy footsteps in the stairwell on Jan. 26 and walked into her kitchen in time to see a blade chop through her door.
She says she was held facedown on the floor at gunpoint while her 3-year-old daughter cried in another room.
It turns out agents were after the other tenant on the floor of the multiunit building who is suspected of dealing drugs.
Sanchez says she and her daughter now have trouble sleeping.
The FBI has apologized and is paying for the damage.