Any hope of getting well water in clay soil?

I just dig a shallow well down to a little over 15'. I hit water at close to 15 feet. I think I can dig 10' more without problem. But what concerns me is that the soil seems to be mostly really fine clay. Actually, when I dug down to 15' or so, I didn't even know that I hit water. I took a long rest and when I came back, I found water.

So, is it still realistic to expect, say, 1 gpm or even a quart per minute from this well (when it's dug down to about 25')?

By the way, the hole I dug is 6 ID.

Does this help?
http://groundwater.ucdavis.edu/Publications/Harter_FWQFS_8086.pdf

Here's a test you can run

Well diameter= 0.5 foot
Water depth= 15 feet
Well water volume [V]= 22 gallons
Well input/output [IO]= 1 GPM

user demand [D, D>IO]= 2 GPM
output duration [OD] = V/(D-IO)
OD= 22 minutes
output gallons [G] = OD x D
G= 44 gallons

Fill the hole with water from another source. If it won't take water, it won't make water.