I'm no breast feeding expert, but I found what worked with my two was to forget about the clock and follow bub's cues.

All babies are different, some only go 1-2 hours between feeds, like my DS2, some go longer.

Obviously, at this age I wouldn't leave her more than 5 hours between feeds, but other than that forget times and how long between feeds and just go with it.

All u need to do is trust your mummy instinct