Yes, often the one breast that had a hematoma will often stay swollen longer. It is hard to predict how long that will last.. Best of luck.
I am sorry to hear about the complication you have experienced. The side that experienced the hematoma will certainly demonstrate increased swelling/inflammation compared to the side that was complication free. How long this process will take is hard to predict. Given your concerns that one side remains "way bigger", I would be concerned that residual fluid is around the breast implant; if so, this can be problematic (actually causing further problems down the line). Best to have your plastic surgeon evaluate you for accurate assessment, advice, and/or meaningful reassurance/predictions. Best wishes for an outcome that you will be pleased with longer-term.
There are different stages to the typical recovery from a breast augmentation / breast implant operation. By the end of the first week postop, a good amount of the swelling and discomfort have resolved, but the breasts will probably look somewhat "high" and feel "stiff". Most plastic surgeons will release their patients from all restrictions by the end of the first month postop, with the incisions well healed and everything settling into place. But the breasts don't usually "drop" all the way until some 3+ months postop. They will also get progressively nicer, more bottom-filled roundness, better softness and more natural feeling during over the 3 - 6 month postop time frame.