Drop in supply

Freaking out because I don’t remember this ever happening with my first born... I’ve been back to work over a month, baby is 4 months old, pumping 2-3 times a day (depending if I go nurse her on my lunch break or if she takes a bottle). I was producing so much I would have excess to freeze. This week I developed a cold (haven’t taken any medicine, not sure if it has anything to do with it) but I am all of a sudden barely pumping a total of 4 ounces between 2 sessions. Has anyone had this happen? Any tips on increasing supply? At this point I’m cutting into my freezer stash and don’t even have enough to feed baby while I’m away