Levothyroxine dose adjustment

Hello 

Can anyone please tell me is it necessary to do blood test for tsh after 6 weeks? 

If I go for the blood test for tsh after 2 weeks?

And does the tsh value reduced first then stable?

Please tell me 

Because I did the tsh after  2

weeks and my tsh value reduced further from 0.03 to 0.02 

I don't understand all these things.

Please