Why do I feel depressed

I don’t know really but nowadays I easily get lonely, worried and hurt even with just petty causes. I also easily cry and get angry for some petty reasons and I just could not understand my behavior. I felt lonely maybe because I isolate myself from my friends and its maybe years already that I have not really get out with them and just talk. I’ve been busy with work and with my children that I have no time for myself. I realized that I am a person too who needed a break once in a while. I’m thinking ways to get myself learn new things and to have new friends even online for mothers like me. I also realized that maybe I’m suffering from post partum blues that mothers like me who had just given birth have experienced. I’ve also talk with my co-worker who has also recently given birth and she felt the same. I must pray always and calm down and condition my mind that god loves me. That I’m not omnipotent and that I don’t hold everything on my hands.