Not producing enough milk 5 days pp

My baby eats constantly it feels like. I know they should be eating 8-12 times a day but she eats like 15-18 times a day ... she poops a TON of yellow seedy poop (already had 5 or 6 poops today and it’s 8pm) so she’s getting enough milk I’m sure but still. My breast pump came today and I pumped for about 15 min and only got a half oz combined from both boobs. Is that enough? I’m starting to drink more water now but Im scared it isn’t enough