Your yield being enough for a single bowl sprinkle could actually be a normal yield from such a small wash (remember as well, you need to wash the same material many more times than once! This applies no matter what you use to agitate your material, you will never get all your hash in the first agitation!).
You can also get very low yields very easily from less than outstanding flower that is not visibly caked with a lot of trichomes. You broke your flowers up enough to begin with for sure, no problem there. BTW, you do not want a paint mixer, drill or any other similar device. What you want is a bubble washing machine! It is very hard to reliably get full melt from manual agitation as the nature of the agitation is not so repeatable.
When I discuss too much agitation, what I mean is you are smashing up the rest of the buds (not the trichome heads) and as a result you get contaminated hash full of ground up plant material.
A justifiable amount of very high end flower for a bubble wash is easily 5-10x as much as what you used, and ideally on the much higher end of that figure. If the flower was immature when harvested, you will not have many trichome glands to get out of the flower. Immature glands are like immature fruit, they are harder to shake off the plant than the ripe ones - too much shaking breaks up the other plant material and before long you have finely ground herb, not hash in your bags.
Can we start with some pictures of your starting flower? It is important before we get any further into other troubleshooting to see that your starting material was worth running. As a general rule, if it is not absolute fire flower/sugar trim that you have on your hands, then it is not worth running into bubble hash. Bubble and dry sift are only effective for collecting the lion's share of the capitate stalked trichomes (these are the trichomes which look like a ball on a stalk) found on your flowers. Some varieties have less of these trichomes compared to the other kinds which are less easy to collect with hashmaking techniques. into late flower bFlowers that are not taken wellefore harvest will have immature resin production (much less trichomes overall, less resin inside the trichomes and the trichomes are much harder to remove from the flowers without taking along inactive plant contaminant for the ride).
I am sure one of the mods can move these posts into the 'school me on making bubble thread', I'll tag
@momofthegoons here to see if she will kindly oblige
Also one more point, please quote or tag me when you reply to my posts. I did not get any notification for this reply and it is very easy for me to miss your questions if you don't notify me.