Mom knows..

I think my mom knows I masturbate... my bed creaks when I do and I try and stay stiff to keep it to a minimum but my walls are hollow... what should I do? I hate the thought of her knowing. I would do it in the bathroom but it’s just as loud. I feel like I can’t do it without someone hearing and it kills my buzz and makes me scared. I’m a female FYI. Any suggestions?