First time stay at home mom feeling exhausted

Looking for some support/advice from other stay at home moms here.
My baby boy is 5 months old and I've quit my job and stayed home since the day I was pregnant. I'm exhausted lately and I don't know what to do. I feel so incompetent that I stay home with only one child and he is still an infant and I'm already this tired. 
Husband is super busy at work but he helps as much as he can. Even tho he can only takes care of the baby for like 20 mins at most every day. Baby is already asleep when he's off work sometimes. He helps wash dishes and bring food home so I don't need to cook everyday. 
My family is 5000 miles away I only get to see them once a year. And we just moved and I don't have any friends in town. 
We just hired a cleaning lady to clean the house twice a month. 
I don't know if I'm just tired or lonely or simply need some sleep. I'm really disappoint at myself. I love my child more than anything but I also feel trapped at home and everyday is just routine now. Should I hire a nanny to look after the baby maybe couple hours a week or something? Thanks for your reply in advance.