All of a sudden I have a crooked smile, why and what to do? (Photos)

Your right side is actually the weak side.Noticing this 9 months after a treatment makes it much harder to speculate about a cause.  There are ways that Botox and fillers intended to turn up the corners of the mouth could have an impact on your smile leading it to appear crooked.  However, if that were to happen it should be something that happens soon after the injections. I would recommend checking with the person who did your injections.  The first step in figuring this out is to know exactly what was injected and where it was placed.  You also need the person evaluating you to have a good understanding of the anatomy of the mental nerve as well as its origins within the entire course of the facial nerve to properly assess your current situation with new onset weakness many months after a procedure.

An asymmetric smile can be seen after Botox injection to the DAO muscle (performed to raise the corners of mouth) if the Botox diffuses to the adjacent DLI muscle. That being said, this would typically be seen within 2 weeks of the injection being performed and not 9 months later. I would followup with your injector to discuss your issue.  

You probably had Botox injected to the right depressor labii inferioris muscle that usually pulls the lip down. This can be corrected by injected 1-2 units on Botox to the left depressor labii inferioris muscle to weaken it and balance your smile.