I dunno dude im not very experienced but can you tell us some more information cause it hard to tell with what little info we know. By info i mean nutes, water, ph, lights, and ventilation shit like that
It might be from how it is positioned under the light(s) or it could be how it was placed in the soil. I have one growing right now (about 3 weeks along) and it started growing crooked. It's trying to straighten out and now it just seems to be a slight curve. I have to run errands but I can get you some pics shortly.