It's early enough in the cycle there is no affect on the potency at all. There are many other things that affect potency and THC content. Cropping in the early stage is not one of them. It will retard (slow down) the vegetation process by about 10 day's to 2 weeks. Some strains even take longer up to 30 days but the extra yield is worth the time. You just need side room. The plant will grow out more then it will grow up.