3 months since I received my botox injections, but my facial features are now somewhat asymmetrical? (Photo)

Botox results last up to 3 to 4 months and can be softened with Venus Legacy and Thermage treatments. I recommend getting a formal evaluation with a cosmetic dermatologist. Best, Dr. Emer

Botox generally lasts 3-4 months, however, there are patients where it may last as long as 6-7 months (slowly resolving).
I do not think it is Bell's palsy with your injection history. It seems that a few fibers of the Levator labii superioris and Zygomaticus major and minor muscles are weakened by the Botox.
It should return to normal over the next few months.

Dr. T

Botox results are temporary and typically wear off over 3 to 4 months, though that can vary by patient. There is no reversal agent for Botox. I encourage you to speak to your primary care physician if Bell's Palsy is suspected.

From your photos, the weakness of your left sided levator labii musculature is noted. Botox is a toxin produced by the bacterium Clostridium botulinum which temporarily paralyzes muscle into which it is injected for a period of 3-4 months. On occasion, the toxin may drift a distance away from the injection site causing unintended weakness or paralysis of the involved musculature. The levator musculature is in close proximity to the eyelid muscles.There is no way to reverse this temporary weakness. Over the next month or so, the effect should dissipate.Bell's palsy is another possibility but the timing appears significant, suggesting cause and effect.Practice exercising your oral musculature in front of a mirror several times / day. This phenomenon should totally resolve.Best wishes...