Sleeping habbit or problem? iin?

my names paloma i have a problem or atleast i think its a problem. Ill start from night to day!
at night i have the habbit or problem of not been able to sleep till 2, 3, 4, or sometimes 5 am. and sometimes i sleep at 1am. or 12am. but the results are always the same, i only wake up because of my baby, even before i had my baby i did the same. am only 19 years old and my baby 5 months old, so its always been a problem. No here is where the problem i think is! i try waking up because of m baby,i could say he wakes up at 5am. so i put him back to sleep and i go back to sleep it doesnt pass 10 min when we are already sleeping then, he wakes up again in 3 to 4 hours and give him formula to put him back to sleep it doesnt take 15 min when we are back to sleeping and i keep the same till its 2 or 3 sometimes 4 pm. sometimes i sleep all day since 12am till 2, 3, or 4am, but i usually dnt have anything to do all day sometimes i exercise, sometimes i clean, sometimes i even play with my baby, sometimes i am in the computer. no matter what i do its always te same. Is it a problem some people say its normal but i dnt. is it?