Can a 3 month old have selective hearing?

[strawberry2017]

My 3 month old had tests today with audiology as we had concerns about his hearing.
He rarely responds to noise especially loud ones, doesn't turn his head to noises or react to his name which I know may be a bit early for.
He passed the hearing test which I am over the moon about but strangely I don't feel very reassured.
Is is possible for a baby to be so chilled out that they just don't respond to noises?
Has anyone got any advice or dealt with a similar situation?
We are due our HV appointment this week so I will speak to her I just need to get rid of this niggling feeling that somethings not right.

My 3 month old startles at loud noises etc and will occasionally look in the direction of a sound but he’t really turn his head to noise or turn to a sound and not his name etc that’s a while off anyway. Dr says this is a 3.5-5 month milestone, some babies do it from birth but some don’t, there’s lots going on for them to focus on. So I wouldn’t worry about the turning to sounds etc yet they’re just getting the hang of hearing at all! x