Sleep regression depression

I'll start by saying my baby boy spoiled us from the beginning. He was ebf for 6 weeks and slept in his bassinet in our room beautifully. We started bottle formula feeding at 6.5 weeks and he is now on formula full time. He has continued to sleep fairly well until now. He turned 4mos on Friday, but has been waking at 3, 4, and 5am for the last few weeks. He used to do 9pm-5am without issue. Now hes awake for at least an hour (trying to self settle, playing with his feet and babbling) between 3-4am. Then if he cant fall back to sleep he cries and I have to bring him into our room in his rock and play. He falls asleep fine and without issue just grumbles for a few minutes. I'm at a point where I want to pull my hair out. By this age with our oldest dd she was sleeping solid 10hr stretches 😭.