Milk supply?

Lizette
Is it normal that my sons 2 weeks shy of being 4 months and I still only pump around 25-30 oz a day ? Do I have a low supply I mean he usually still just eats 3-4 oz every couple of hours but I see all these mamas making 70oz a day and I'm only making half of that I'm so confused lol i do keep up w my sons needs also i rarely have to supplement and I have Only stashed 230 oz so far should I be doing something different ? Or is my milk supply going to boost once he starts asking for more milk