9 months wake up at night

Hi mummies i need help! Anyone out there experience LO waking up at night crying and wants to be rock back to sleep?Day time he will nap total 3-4 hrs and yes we usually put him to sleep by rocking him. If he wake up i will just pat him n he goes back to sleep.Used to sleep well and only having 1-2 feeds at night but now it seems every night he will wake up crying and it will start only about 11pm onwards.His bedtime will start 730-8pm. Give him milk but he doesn't want it and keep crying. Day time granny is taking care of him and he is ok. Check tummy diapers temperature all okay. LO will be 10 months in 2 weeks time. Is it normal or i need to be worried?