why is HR soooo slowwwwww

I got a call from the HR of this company I used to intern for saying they will be posting a job and they want me to apply for it and that they'd email me once it's up. Literally my dream job, but it's been 7 days and still no job posting nor email. Maybe I’m just being impatient.

Does anyone know what's going on behind the scenes? When should I follow up? (if at all) After how long should I accept that they went a different direction?

I've been unemployed since June and the depression and anxiety really eats away at me sometimes.