How Long Do Effects Of Eltroxin Last In Body?

Hi Doc I had to have a thyroid lobectomy 6mnths ago and the surgeon put me onto Eltroxin a week after. In Jan I saw an Endo and she tested my T3 and 4 and they were functioning properly so she halved the dose for 6 weeks when I had bloods tested again. They are still normal so have now stopped Eltroxin. I have gained a lot of weight over the past 6 months have experienced swollen lips and eyes, have been very tired whilst on the meds. How long will it take for the Eltroxin to work out of my system and should the other symptoms stop?