1 month old constantly crying. Help!!

My daughter is 1 month old and will not stop crying, she will be fed and a clean diaper but as soon as I lay her down she will cry for hours and not let me do anything. I have 2 other kids to tend too, it’s so overwhelming. Plz don’t judge or be mean just let me know your guys experiences if y’all had any or what y’all suggest I can do?