Boss refused wages because of my medical needs.

location: oklahoma

i (28f) work at a very small insurance firm, for many reasons i will not state, my health is declining, and im having to see a lot of doctors, having procedures and surgeries done. i make sure to plan my appointments for the morning so i can go into the office for the rest of the day and my boss always knows about my schedule. recently i had an emergency that required me to be out of the office, short notice, for two days. i guess that outraged my boss. during a meeting last week she announced that my wage was to be cut because of “shift of you inconsistent work schedule” i was stunned, i have noted and proof of reason for all of my missed days. she was upset im not working 40 hours a week and im no longer dependable because of my health. i made her put this in writing, and i wasnt going to sign it but my employment was further threatened if i didnt sign it. is this legal? where do i start? where do i go? i’m not offered any sick days, fmla, paid time off, no benefits or anything like that before that is asked.