What Causes Swollen Eyebrows After An Injury?

Hi, last night my 7yr (small) son hit his elbow directly to my eyebrow. Once he hit it I honrsth started crying (but hid it) the went to the bathroom to make sure I wasn t bleeding. Now today people are noticing my eyebrows are not the same (ones swollen) obv ones sensitive.... I honestly want to know what s up w my eye?