The first possibility that came to my mind was that perhaps the curve was already there, and since you have begun a PE routine, which naturally will get you a lot more intimate with your penis, it is possible that you were unaware of the curve previously. This type of realisation is not uncommon when beginning PE. Many men have a slight curve to the left due to the fact that most men use their right hand to masturbate which does cause a curve to the left in some men.
It is also, I suppose, possible that you jelqing has some brought out a dorment curve (caused by right-handed masturbation) by some fibroblastic mechanism, or otherwise. That’s purely speculation though.
Have you noticed any other changes at all regarding the curve? Other than perhaps slightly annoying you, it doesn’t sound particularly serious. That being said, you should keep note of it and if the curve becomes mroe severe or starts to show in your erect penis, it could be that a plaque or somesuch is developing, but I don’t think that’s likely.