Its totally normal! Mine seemed to disappear around 13/14 weeks, I hadnt had any MS but I had awful headaches and sore bbs. They say you start to feel way better during Second Tri and that is just starting to happen for me now. I still get occassional sore bbs but other than that, I wouldnt even know I was PG (if I didnt know). I was so worried for my 20 week scan because I just felt so normal but little man is growing fine and is a right little wriggler.
Try not worry and enjoy the respite from all the icky symptoms!
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