I didn't even notice to be honest but i'll take another closer look next time I go out to check on her. But I do think it probably is dirt. It amazes me how quickly they grow once the leavves come in. So if tomorrow is exactly one week since she broke soil, still wait until day 10-14 for any nutes?
Pot feeling a little light so I may do a small watering tonight or tomorrow. The guy at the seedbank today told me "always remember, marijuana plants don't like their feet wet" lol