Suggest Treatment For Stress Fracture In My Foot

I have a stress fracture in my foot and I just found out I'm pregnant. I'm in a boot and I'm taking Ultram 2x day and Percocet, 1/2 tablet at a time 1-3 times a day. I can't be more than 4 weeks along. I only take the Percocet when I need it which is usually at work, and that is because the pain is intolerable. Is this ok?