Artemisia annua grow experience. know your dealer, watch out for your seeds...and stems

About 6 weeks since the first sprout. There appears to be heavy contamination with an unknown weed variety. Due to its density and pen point location I'm pretty sure the seed packets themselves are the source. I ordered over 35000 seed from 4 different sellers, sold by weight. 2000 = 1 gram approximately. I had difficulty getting anything the sprout at first, soil improvement solved that but the number of Tru Artemisia I will end up with remains unclear. I am now growing the mysterious weed plant as well. In hopes of identifying it's source