Help!!!! Sleep training

My son good now about falling asleep by himself when he first goes into his crib takes him about five min to fall asleep but after a couple hrs he just will not go back to sleep like he will only sleep with us in our bed even if I let him for a fifteen min time he gets wicked upset and all he wants is me in his mouth idk what to do or am I messing everything up for him I feel like I’m horrible it’s also hard because he does not have his own room and probly won’t till 17 months