Thank you for checking out The Baby Sleep Site! I’m sorry to hear you’re having so much trouble with sleep. Based on your comment, it does sound like your little one might be coming into the 4 month sleep regression. We have an article with a lot of information on that here: https://www.babysleepsite.com/baby-sleep-patterns/4-month-sleep-regression/
"I tried Tracy Hogg's approach: Don't leave the baby to cry! Instead, when he starts up, go in there, pick him up, and love him until he stops. Once he's calm, lay him back down. If he starts crying again, repeat. Eventually he'll know it's time to sleep. Hogg said she had to do it 126 times with one child, but it dropped to 30 the next night, four the next, and soon she didn't have to do it at all. I tried this with my 3-month-old and it worked like a charm!"
"My first daughter was sleeping through the night (10 p.m. to 9 a.m.) by 6 months. We had a complete bedtime routine: a bath, a book, a bottle, then to bed, a little music in the crib, and asleep in 10 minutes. It was wonderful, but that scenario didn't work for my second daughter and hasn't worked for my son, so I've tried different things for each of them. Sometimes a plan doesn't work. Listen to your baby – he or she will tell you what you need to know."
"No Tears" Techniques: Just as some parents and experts believe that it is harmless to allow an older baby to cry for set periods of time, others prefer sleep-training methods that gradually teach the baby to fall asleep without Mom or Dad’s help. For example, one "no tears" method involves sitting in a chair next to the crib while the baby falls asleep, and then, each night, moving the chair farther from the crib until it's in the doorway—and then, finally, outside the room.
This is another gentler technique. The PUPD method works just the way it sounds: when it’s time to sleep, and your baby is fussing or crying in his crib or bassinet, you pick him up and comfort him until he’s calm and drowsy. Then, you put him back in his crib to sleep, repeating this cycle until your baby is finally asleep. PUPD is another method that requires quite a bit of patience, depending on your baby, and it won’t work for every baby; some babies find being picked up and put down so often over-stimulating, and they gradually become frustrated and worked up, instead of relaxed.
After going through your bedtime routine, put your baby in their crib, leave the room and wait a specific amount of time (say, a minute). Then go in and reassure your baby with words like “Mommy loves you” or some kind of touch, such as a rub or pat. McGinn says it’s preferable not to pick the baby up. Garden, on the other hand, reserves this method for babies seven months and older. (In her opinion, younger babies require a parental presence so they know they haven’t been abandoned, especially if they’ve worked themselves up into a frenzy.)