Normally a combination of synthyroid
and cytomel would be given. If you are taking
cytomel, it should also be spread out through the day (ie. multiple dosing) not all at once.
I would be rechecking on this or getting a second opinion. Another option considering that your FT3 is low is to switch to 'natural thyroid' whcih contains T3, T4 and other trace hormones. Armor is one, dessicated thyroid (erfa brand from canada), or compounded from pharmacy.