bubbles while pumping

Courtney • 👨‍👩‍👧➕👶
I am pumping right now and in the funnel part I have bubbles coming out in my breastmilk. There are none in the collection bottle and it is not soap because it only started towards the end of my pumping session. Anyone know why this is happening? I possibly have a mild case of mastitis, could this be the culprit?