Hello
You can use FMLA and STD (Short term disability) together; actually they have to run concurrently. The FMLA is a protection for you that holds your position for 12 weeks, and the time taken off can not be held against you for disciplinary reasons. FMLA is unpaid, but WLS is covered by most STD policies and you can receive partial pay while you are out.
My company does a 60% pay for STD, the first 3 days are not covered but if you have sick, vacation, or personal time you can use that during this time. Then the rest they picked up for me. I took 2 weeks out of work when I got banded, and then 3 days when I had my port moved.
Feel free to e-mail me directly with questions about FMLA, I work in HR and this is what I do most of my day :sick