You will get there but it will take a while to get things right in your body.
Thyroxine has a long half life. This means your bloods may not show "correct" levels till around 6-8 weeks. And this may still need some adjusting. You should be being asked to return for blood tests soon to check current levels.
What was your tsh?
For pregnancy ideally tsh needs to be below 2 iirc, most places would prefer 1.
The reproductive cycle can take around 3-4 months to properly reset after any major changes. The book "it starts with the egg" describes the impact on egg quality of any additional vitamin eg folic acid as taking 3 months.
The best thing to do would be to eat really well, take the recommended folic acid and vitamin d.
Thyroid patients often need other things like iron, zinc, b12, folate and vit d too. You could take an all in on preconception multi vitamin but be very aware that you must take within 4 hours of your thyroxine.
>>You must stop any vitamin with biotin in for a good few days / week before a thyroid test.
>>Always have your thyroid test in the mornings, around 8-9 am. Take the thyroxine after the test.
>>keep a very consistent routine for taking the thyroxine. 30 mins to and hour before breakfast.
It might be best to focus on overall health and well being for a good 6 months when everyone is balanced before you think about conception.