depressed after baby

I feel so depressed. I had my son almost 4 months ago. He’s my world, I love him more than anything and I feel guilty that I feel like this. My relationship with his dad isn’t the best it could be. He doesn’t work. We live with his mom and we’re 21 & 22. I just applied to Walmart bc I need to provide bc clearly I can’t depend on his dad to, & need a job fast. I’m thinking of college also. I spend every moment with my son. I never have a day to myself & the days just run together. I don’t feel beautiful anymore. I don’t feel healthy. I hate looking at myself in the mirror. I hate waking up some days bc it’s just the same thing all the time & I hate myself for feeling that way. I love my son so I don’t know why I wouldn’t want to wake up. I just want things to change or I’m going to lose my mind.