HELPP! Diminished supply

I am 8 w PP and I have been EBF. Started a period? (light bleeding) a couple of days ago, and since then my supply has drastically dropped. I have always had an oversupply and now the only time I have a decent supply is first thing in the am. The rest of the day baby seems unsatisfied and I have to feed from both breasts and it still seems like he isn’t getting enough. When I pump I am only getting 1-2 oz. per breast when I normally get 4-5. I’m assuming this is due to a hormonal shift? Anyone experience this? Advice?!