Grip and Hand Pain

So for the past three days, I have been clearing brush by hand (since my husband and I both keep forgetting to get bar oil for the chainsaw). This has been three solid days of handheld pruning shears, a machete, and a hatchet. I've managed to clear a little over 1/2 an acre by myself so far.

The issue? My hands are shot. I've had a death grip on these tools for three days now and unclenching my hands takes some serious concentration. Needless to say my wrists and shoulders hurt too, but I can foam roll those and move on (as long as my arms don't need to go over me head for a little while....)

I'd like some sort of stretching/unclenching ideas for this weekend (I still have about two days of clearing left) so im not completely useless next week.