I worked on my salvaged mirror for 3-4 hours before my back just gave out on me. Perhaps there are a few stretching exercises that I can do that would help this. Usually I get up and do household tasks such as filling the dishwasher, or perhaps washing clothes. It just seems to help to move around a bit.
I made good progress as you can see. I continued to fill in the spaces between the vines with colored glass. Most of this glass was still on my table just waiting to be used. Occasionally I would dip into a container with miscellaneous glass for a variety of greens, yellows, golds and browns to make up the sections of vines.
Here are the pictures of the finished, grouted tea light holders with the heart motifs.