Maternity Leave/Short-Term Disability

Eva
Needing some advice, and hoping someone can help.
I work for a small company and we have less than 50 employees, so I do not qualify for FMLA. I also live in Oklahoma, and unfortunately this state does not have any laws regarding maternity leave other than FMLA. However, my employer offered short-term disability through UNUM. 
Long story short, I had to have an unexpected c-section due to complications during labor, and after submitting my claim to UNUM, they only approved me for 6 weeks of short-term disability pay, even though my doctor ordered me to return to work after 8 weeks. UNUM advised they would do another review after my 6 week appointment if my doctor sends in a request with records.
I let my boss know about this, and told her even if UNUM does not approve the full 8 weeks of pay, that I will take the last two weeks without pay. Well, now my boss is telling me they're busy in the office and will need me to return to work if UNUM does not approve the full 8 weeks, regardless of my doctor's orders.. This just does not sound right to me. 
I'm currently still looking into all of this to see what laws I may be protected under, but does anyone have any knowledge/advice for a scenario like this?