total calories

Ok guys I am new to the community but I have been using my fitness pal for several months. I have lost 45 lbs but now have seem to be at a stall! I have not lost anything in over a month. Let me give you a little background. I started out 6 months ago weighing 256 at about 5'4 and will be 40 next month. I sit at a computer all day at work. I now weigh 211-212 ( depends on which day I weigh in LOL) have worked up to where I can walk 3-4 miles at a time, work out approx 60 mins at a time, even worked up to jogging some
( sweet Jesus i never would have believed it!) I am down from a size 22 pant to a size 16 pants. But for the past month i have really gotten down because I have increased my walking (thats where the jogging has come in and the extra miles) i have done more of the ab workouts, walking trails and just all around more active. I am wondering if I am really not eating enough calories. I dont think I really started out eating enough to begin with. I do have a thyroid problem and I go to the doctor regularly so he is aware of my weight loss and what I am doing so it is nothing unhealthly. But last month I started breaking out in hives and I thought it was my thyroid medication, at that time I was busy thrying to get ready to go on vaction and didnt have time to get to Dr. and he couldnt get me in anyway so I just stopped taking it till I could get back and get in to see him. When I did get back I went and saw him and he increase my thyroid medication ( btw my thyroid is underactive) and so I am also wondering if my lack of weightloss is due to the increase in the medication this month. It is not only am I not seeing it on the scale but I am not lossing inches either. I went back and changed my goal in MFP and changed how many times I work out a week because I think maybe I was walking everyday and so I was walking off after already not eating enough calories if 1200 was not enough now that I look back. IDK ,,, what do yall think? I am afraid that going from 1200 calories to 1530 calories is going to make me gain weight now because that is what it is telling me my calories a day are now.I need some advice! I have come too far to get discouraged and quite now! I have been over weight my whole life and to loose that 45 lbs has felt wonderful I would love to loose 50 more lbs I dont want to set goal to high but I have really gotten to were I love to exercise and I never would have thought those words would come out of my mouth! We live in a small town, cant really afford to go to the one gym in town and I cant get anyone to exercise with me and trying to make sure i get house cleaned and daughter & hubby's supper done and still make time to take care of myself and not put myself on back burner which is what got me here in the first place has been a challange but I have made a promise to myself! Sorry this is so long! PLEASE help me out!!!!!!!!!!!!!!!!!!!!