When my DD18 months was a new born.. I found the 1.5 hr awake time to be very true. I worked on this time frame too and she soon turned into a great little sleeper. It is likely yr Bub has not learnt day from night also at this young age. I liked to darken the room to indicate sleep.. Gave her a dummy and later a cuddle toy. She still loves her cuddle toy and won't go up bed without it. By knowing subtle hints of her getting tired.. And using the 1.5 hr guide.. I would put bubs into the cot awake she would self settle. It does get easier as bub gets older. I remember that first month being a blur.. With all the sleep deprivation.. Luckily for me.. As a single bottle feeding momma.. My bub was sleeping 8 hrs overnight from about 8 weeks.. Which then progressed to about 11 or 12 hrs overnight from 10 weeks. Good luck!