One Side of my Face Lower Than the Other?

100% of people have facial asymmetry and it's important to remember that while this can be corrected and improved, I tell all my patients that there is asymmetry to the bone, muscles etc. The same way you are right-handed or left-handed, when you smile the muscle attachments and skin attachments are different explaining why some people have smirks, dimples etc. The asymmetry is more prominent in some people than others.  There are things we can do to make things better, but at the end of the day, I tell my patients there's a 100% chance they will still be asymmetric after any surgery anywhere in the body. We usually try to make people more symmetric especially if it is something that bothers them. Sometimes people only want a facelift on one side or certain procedures without targeting both sides of the body, and this is something that is available and possible.
If you are concerned by your facial asymmetry, I would recommend that you see a board-certified plastic surgeon in your area that is a member of both ASPS & ASAPS and performs a lot of facelifts but also offers all the nonsurgical options such as Botox injectables and laser treatments. Sometimes injections and nonsurgical treatments can improve asymmetry without any surgery.  
I hope my answer helps you. If my answer helps, please take a moment to up vote this answer on the “respond” button on the top right.  Have a great day.

Facial asymmetry is a common concern and can be influenced by various factors, including dental alignment, muscle tone, and underlying bone structure. At 26, you’re likely not a candidate for a surgical facelift, but there are non-invasive and minimally invasive options to address your concerns. Consulting a dentist or orthodontist about potential misalignment of your teeth might be a good first step, as this can sometimes affect facial balance. Additionally, aesthetic treatments such as neuromodulators (like Botox) or dermal fillers can subtly enhance symmetry by relaxing overactive muscles or adding volume where needed. A personalized consultation with a facial aesthetics expert can help determine the best approach for your specific goals.

This is a great observation!
It is actually amazing, but most people have facial asymmetry. It is what makes our faces unique and different. This is why the simulated photos where they mirror one half of the face on to the other side often look quite abnormal and unnatural. However, there are certainly some people with more significant asymmetry where things can become bothersome. For these issues, consultation with a plastic surgeon can help determine if these asymmetries are within the realm of normal asymmetry or whether they are more severe and could benefit from a potential intervention.
Hope this helps!