Paul Cashmore might need surgery on his face after he was punched multiple times in the Pennfields area of the city by an unknown man.
The 49-year-old said he was offering help to a young woman in Lea Road who appeared to be in trouble, before a man ran out of a house, across the street and attacked him.
But he claims to have heard nothing from the police about the investigation – and said now he is afraid to leave his house.
Mr Cashmore, who lives just round the corner on a street off Lea Road, said: “I was just going to the shop for some cigarettes.
“It was about 10pm and I saw this young woman in her pyjamas curled up in the bus shelter.
“I didn’t say anything at first but when I came out the shop I asked if she was OK.
“She said not really but she asked for a cigarette.
“As I was handing her one this man ran across the street and shouted, asking what was I saying to his girlfriend.
“He then punched me in the face. I had two broken bones and a ruptured eye socket.
“The hospital said I might need facial reconstruction surgery.”
The attack has made Mr Cashmore, who is a caretaker at The Khalsa Academy in Millfields Road, afraid to leave the house.
And now he has become frustrated that the police have not kept him informed on how the case is progressing.
“I keep ringing them. I was on hold for 22 minutes the other day,” he added.
“I’m nervous to go back to school for my work in September with all these bruises.
“My employers have been very understanding but it’s still frustrating.
“I had to cycle past the attacker’s house the other day – I feel like I’ve lost faith in the police.”
West Midlands Police have confirmed officers are investigating the assault which happened just before 10.10pm on August 9.
A force spokesman said that a primary investigation has begun and another statement will be taken from Mr Cashmore in the future.
He said: “It’s believed a 49-year-old man was punched and knocked to the floor by another man who fled the scene with a woman.
“The man was taken to hospital to be treated for his facial injuries, that are thankfully not believed to be serious.
"A primary investigation began while the victim was in hospital and a statement from him will be taken in due course to progress the investigation further.”