Could Increase In Weight Be Due To Diotroxin And Hormone Repair Capsule?

I have been on eltroxin .075mg and have changed to diotroxin for the past three weeks.My doctor also prescribed a hormone repair capsule.I am 56years old and am currently using the evorel 50 patches which my gynae prescribed.My doctor also gave me a vitamin D capsule as well as salmon oil 1000mg as well as kelp.I have found that I have gained 3kg in 3 weeks.I am very unhappy with my weight gain as I am not a reckless eater.Please advise me .I first had an overactive thyroid for which I received nuclear treatment and now my thyroid is underactive