Blue veins/bruising under eyes rapidly more noticeable. some swelling under eye. what could it be and can i fix it?

Head injury?: If you have bruising under both eyes and have recently had a head injury you need to get checked out by a doctor right away as this could be related to a skull fracture. If you just notice prominent blood vessels under your eyes this is a cosmetic issue you should talk with your doctor about.

Allergies: Usually this is a sign of sinus congestion from allergies.