Syd try & drink some Cranberry juice as it's good for kidney infections, and don't worry about thyroid I have had an underactive thyroid since my early 20's the last scan showed my thyroid was pretty much gone (I have thyroid antibodies) I see my Endocrinologist twice a year, he increased my daily Eltroxin by 25 last 2 times I got a BFP. He said once they know you have it they can manage it. He also got my blood tested at 5 weeks and then planned to do it every 5 to 6 weeks. Make sure they test Free T4 and Free T3 as well as TSH, as the Pregnancy hormone hcg can cause an incorrect false low on TSH. His target was to keep my TSH around 2 during pregnancy and my Free T4 towards the upper end of the range. Stay positive xxxx