sleep training

I'm breastfeeding and my 4 months old baby eats every 3 hours during day time. When she was 8 weeks old she used to eat more often and give me 7 hour stretch at night. Right now she wakes up every 20 min during naps I let her cry 5-10min and go give her the binky. She can wake up 3 times. At night she goes to sleep at 8pm, and wake up crying at 11pm again binky and back to sleep .At 1 am she wake up and i feed her. Back to sleep, and wake up screaming at 2am, binky again. Then around 4.30am feed until 7.30 am when she finally wake up happy. IDK what to do im going crazy with this. She used to sleep so good. HELP!!!!