I'm a failure

I just caved. Told my husband to make my 4 week old a bottle for the first time. I'm so upset with myself but I don't know what to do. My little one has been feeding non stop and won't go to sleep. He hasn't slept all day and I've been trying to put him to bed for 4 hours now and he just screams every time I take him off the nipple. I don't think it's my supply/ I think he just snacks all day so he's always hungry but I haven't slept or eaten anything of substance all day because I can't feed him and me at the same time... my husband thinks that if I can just get some rest then I'll feel better but I can't stop crying. I think I have ppd anyways and this just makes everything worse.