cycle going nuts?

Demet
Hi everyone, on the 2nd month of ttc last september, i suddenly got sick and got diagnosed with hashimoto's thyroiditis..Last month was the first time my tsh level turned out within normal range. And this month my cycle suddenly fell to 28 days from 33 days!! I no longer have any idea about myfertile  window or whether to start ttc again... my doctor doesn't really encourage or discourage me. Anyone with similar experience out there??