My DS fed every 2 hours through the day til he was 8 months old & alot of the time after 10 weeks fed every 2 - 3 hours over night too. He has only started sleeping through the last few months. Every time he seemed to settle into a pattern something would change it.
Could be good to talk to your MCHN, but be ready for her to say you could start introducing formula. This is normal for a baby. Don't let her try to convince you otherwise. Just a warning