Scallop Squash Conumdrum!

The newly forming male flowers on my scallop (patty pan) squash look 'odd' - they don't appear to have any petals forming and look very different to previous male flowers. Is this normal? I have harvested my first squash and there are more fruits firming. I was late in sowing the seeds. They are in a raised bed in the polytunnel and maybe a bit overcrowded.
Any help appreciated.