This same thing happens to me also, I try to get up and move around or watch a bit of TV or even get something cold to drink. Sometimes this helps and sometimes I have to just take a little break or if it is at night I go to bed. It happens more to me in the evening time.
OTN: Several WIPs
Crocheting baby items for a gift shop.
I am yarnin4aproj on Ravelry.
" May every stitch you knit bring you a little closer to that calm, clear space in the center of your soul. --- Earth Heart Designs"