Why did the buffalo hump on my back disappear after taking Zoloft?

I went to the dr. to change my antidepressant and about a lump under my arm. She changed my antidepressant from Paxil to Zoloft. My depression has been where I cannot get out of bed, eating all the time, and etc... Well I was on Zoloft for one day and started feeling so much better. The lump under my arm seems to be shrinking and my husband told me the hump on my back is gone. I felt back there and sure enough it is loose instead of a big hard lump. I actually feel like some kind of weight has literally been lifted from my shoulders. Would Zoloft have fixed something like a buffalo hump? I have never showed my dr. the hump because I just didn't think about it. I have been stressing how tired I am all the time, but nothing has been done about it. My blood pressure is always high too, but she acted like it was good when I know better. When the bottom number is 98 that cannot be good. I am so glad the hump is gone, but I am just curious as to why it is gone. I mean can a antidepressant have done this, or was getting of of Paxil what has done this?