Can you help with bulging eye-bag muscle post-op lower blepharoplasty? (Photos)

This could be multiple things, however, the most likely scenario is that you still have post-operative edema or perhaps the surgeon has not removed all the appropriate volume that was required.

The darkening can be explained as hypopigmentation from the bleeding and bruising after surgery. In this case, some lasers treatments and some products can be very helpful such as Retinol products and IPL treatments.