Talk to Gynecologist on Thyroid And Trying To Concieve

I need a guidance about my thyroid level and concieving , i was trying to concieve for about 5 months but i couldn't, i have my periods on time after every 28 or 29 days cycle , flow is normal, my ultrasound was normal , dr suggest me to go for follicular tracking ultrasound and follicle size was 2.2cm then my tsh test was lie in between 0.65 but dr said it should be 2.5 to 3 for concieving so that I'm little worried about my tsh level and my husband's semen analysis report was also normal but still I'm not concieving please suggest me what should i do my thyroid medication has started about a week ago that is 50 mcg . kindly guide me is there any serious problem or should i need any other test?