How Long Does It Take to Get Out of Your System???

I was on it for only 14 days. started out on 2 a day of 20 mg for 5 days for sinus infection. Then had terrible headaches that ended up in Er. Given antibiotics had allergic reaction given more prednisone. (3 20mg. a day) Following day had another reaction to new antibiotics given another 60 mg that night as well as my usual dosage in the am. Headaches worsen by 10 day on prednisone dr took me off immediately due to severe side effects. Ended up in hospital 3 days later with low sodium counts. Now 3 weeks later being off still have such anxiety, migraines,nauseau Help.....how long does it take. Just saw allergist said could be 4-6 weeks. If prednisone is out it stills causes such problems in body, The body has to balance its way back to normal. Never had I have anxiety, pretty much have no life.......