I was swimming in Strouds Lake at above saw a series of 5-7 square yellow/green squares all moving very slowly and equal distance apart

I regularly take a swim in Strouds Run State Park. I swim across and then return back. On my way back I looked up and saw the sky. It was sunset and dark blue above me. To the horizon was colorful sunset. Above me I noticed thin clouds. I noticed among them were 5-7 square yellow green colored objects. All equal distance and within the clouds. There was no noise. They moved very slowly over head. I could not come ot any other human make objects which they may have been. It was a bit frightening being in the middle of the lake as the object(s) passed overhead of me. I felt am awareness of myself and that something above was looking at me. It was a strange feeling. I swam as quickly as I could back to shore. At this point it had passed and was continuing East slowly over the lake.
More more detail, the green/yellow squares apeared to be blinking.