Two weeks post op total thyroidectomy and weight gain

Hi All,
I just found this site and am so happy I did. I am post op TT 2 weeks now and just had my first endo visit today. The doc increased my levothyroid fron 125mcg to 150mcg due to my hypo symptoms...I have gained 6 lbs. in one week and feel so huge with absolutely no energy. I feel bloated and so sluggish. If I could sleep all day I would.
I had my thyroid removed because I had a 7cm multinodular goiter that was becoming very obstructive....choking on everything I ate and even had trouble breathing when in bed. I was on suppression therapy for about 15yrs. hoping that the goiter wouldn't grow. Unfortunately it did and with it came the choking and trouble breathing.
I have been up and down all those years sometimes hypo and sometimes hyper, and seemed to constantly gaining weight :( about 10lbs. per year (when I was first diagnosed I was 140lbs. and fit, but after 2 pregnancies gaining 20 lbs. each time and getting older I maxed at 220...ugh!!) For a while I seemd to be steady at 220 for the past 3 yrs. until this past year (now at 234). In addition to the weight gain, I have had heart palpitations. My resting heart rate was always around 98 and lately 114-124 at rest. My EKG was fine and I guess the next step would be a Holter Moniter. I was hoping the the thyroidectomy would help it, but that wasn't happening. In the hospital my heart rate was 124. Funny thing is that other than the rapid hearbeat I had no other symptoms until now, easily fatigued and sometimes short of breath. Not exactly sure if the thyroid has anything to do with it, too soon after surgery to tell.
My main concern at this point is the weight gain and sluggishness. In reading all the posts here I have to wait it out until my levels normalize and take it from there until I feel right again. I haven't changed my diet, I do eat healthy, but I don't have the energy to exercise and at this point I don't even feel like I want to. My heart rate does concern me, so I need to take care of that as well.
Have any of you had distrubances in your menstral cycle? I have always been very regular and I'm now since the surgery, 1 week late. My husband and I have had sex only once (I'm not on birthcontrol) and at my age, 45, I know things are slowing down in the baby dept. I had a pregnancy test done today just to make sure. My doc seems to think it's because of the surgery.
They also had to send my thyroid to Stanford to be looked at in more detail. The doc said that it wasn't usual fo the hospital to do this, they couldn't come to a decision as to whether there is more going on than just a goiter. Hopefully no cancer will be found, and if it is, thyroid cancer is slow growing so I don't think I'll have to worry too much about it.
I'm sorry for the long post and if I'm rambling. I hope you understand.