Sleeping schedule

So I went back to work after having baby! My problem is he doesn’t want to sleep early. There is always a time between 9-1am where he cries and cries. You can tell he’s really tired but he doesn’t sleep. He can sleep for maybe 2 mins then hes back to crying. Could this be colic?

This is my second child my daughter is 7 and he’s 6 weeks. I was a stay at home mom with my first so she wasn’t really on a sleeping schedule but since I’m working

This time around he needs to be on one. Any advice?