6 week old constantly on the breast and not sleeping

My 6 week old wants to eat every 30 minutes to 1 hour. She’s been doing this for about a week now. I usually can only get her nap for 10-30 minutes before she’s up and wanting more. Today she’s only napped maybe a total of 1 hour from 8am to 4pm. She’s been rejecting a paci and just wants me. At night we were getting one 5-7 hour stretch and now I might get one 3 hour stretch starting at 8pm or 9pm and then I’m up all night and I might get one more 2-3 hour stretch around 6am. I have two other children that are 4 and 2 and they need me too. It’s been really hard. Can anyone give some advice or words of encouragement here. This is my first time breastfeeding this long and the only time I’ve exclusively breastfed so this is new for me.