Whatever your bug is (and I wouldn't discount spider mites) you didn't absolutely, definitely get them (or not get them) from the person who gave you the clones.
Get the 'scope, figure out what they are and then make sure to kill every last little fucker while your plants are still small. Then kill them again.
I bought one of the USB scopes that plugs into a pc, from eBay. My spider mites were all over the place like pacman, and I grew from seed.