Hello, i've had a lower back pain for almost 4 years now. in the worst cases my left side of my hip swells. i was wondering is i have sciatica.

Possibly: It is possible you have a radicular pain. That happens when there is inflammation in the spinal canal that causes pressure in the nerve that exits the canal at that level and causes pain. Commonly people call it 'pinched nerve'. Sciatica is a type of radicular pain. Hip pathology should also be considered.

Hip swelling?: Hip swelling is not normal for sciatica pain. I would suggest getting evaluated by a sports medicine doctor who has extra training on spine care as well. Otherwise i would see a spine specialist to evaluate the issue further.