Starving my son?

A

I’ve been breastfeeding my son for 4 months. For the past few days he would nurse for a couple minutes and fussy at the breast. Today Decided to pump and I got just 1oz. Have I been starving my son? Should I buy formula? I drink lots of water, blue powerade, oatmeal, lactation cookies.

If I give him formula im afraid i will produce less