Hypothyroid people - What gives?

I've been hypothyroid since I was a teenager.  Before surgery, my TSH was within normal range. (the lab shows .5-5 as normal)  Had it tested last week, and it was 20.  I would have thought with about 75LBs lost since November that the doctor would need to decrease my Synthroid, not increase it.  Wonder what's up with that. 

For those of you on Synthroid, how has your dosage changed since surgery?

I actually started synthroid about a year and a half ago.  I was told it was genetic.  My brother who is 11 years older than me, had to start on it about 10 years ago....perfect genetic replication.  I have several other siblings, parents, neices, nephews...that all have out of whack numbers.  I'm certainly not saying it's always genetic, but in my case I'm pretty convinced.

Weight changes are not always the culprit or the solution.  I know that unchecked, some people will gain weight if they are hypo....or is it hyper....never can remember those words.

I'm not a doctor, and I don't even play one on tv - I don't pretend to understand it all, but I CAN share with you that my synthroid dose was just increased as well, and I've been on in @ 8 years with NO increase!

But given all the other meds I'm no longer on, I'm not gonna complain!

My dose has been changed everytime I have gotten my levels checked since surgery!! I have no idea why but I am hoping it levels out soon!