Your blocks look great! I made blocks like these once. The difference was that I cut out the circle with a pinking rotary blade. Next I placed the circle on a background square that was on top of batting and a backing square. I sewed a scant quarter inch along the perimeter of the circle. Now I had a quilted block. I joined the blocks as you would for a rag quilt.
Have fun playing with your design. I love it so far!