Working mom

I was a stay at home mom for the first year of my baby’s life. He just turned one sept 24 and me and my husband decided that financially for us I needed to get a job. I was looking for one that would allow me to have alot of time with my son still. I found one that works me mon-fri 4:30am-11am and sometimes on Saturday. I thought it would be perfect since most of my shift is while he’s asleep. But This is my first week working and I’m on my feet the entire shift. And when I come home I am EXHAUSTED. From having to wake up still 1-2 during the little time I have a chance to sleep to nurse my son and then having to get up to get ready by 3am. And plus my body is sore. I feel like pregnancy has aged my body and now it’s harder for me to be on my feet all day. I didn’t work for half my pregnancy too so I haven’t had a job in a year and a half. So when I get home all I feel like doing is sitting on the couch and putting on cartoons for my son. And I don’t want to be like that. I want to be able to do exactly what I was able to do for our home and my son before I started the job. I feel like a terrible mom. I want to be able to play, cook, clean just as much as before. So I guess the point of this post is to ask, Does it get any easier? Does anyone have any tips to help me transition into being a working mom now?