your doctor has advised you properly about the dose of her thyroid medication. Low platelet counts are unlikely to be related with hypothyroidism
. It can be due to various other reasons. When you say the count goes up on itself then mainly it is an idiopathic phenomenon- something without established reason. But taking her to a Haematologist will certainly help as I am not able to see the values of platelets you have mentioned here at all. So can't comment much on this issue. I hope you understand. Take care.