Postpartum depression starting at 9 months postpartum?

When I had my baby we were on lockdown and my husband was working from home full time.

I had 24/7 help from him and my mom would come over sometimes to help too.

A couple months ago he started back up at work after being home for 6 months.

My mental health has slowly started to decline since then.

I didn’t realize how hard it would be to be doing this alone all day. Especially now that baby is crawling and needs less naps and way more attention and needs to be entertained.

When my husband was home we could take turns watching the baby while the other does house work or cooks. Now everything is on me all at once.

I feel overwhelmed, touched out and my patience is very low. I don’t feel suicidal or anger towards baby. Just crazy overwhelmed and sad sometimes.

Could this be postpartum depression, or just a difficult transition to change?