I concur with NoMercy plus I would say any vinegar at all. Don't think odour will be an issue past about half an hour, it won't be unless someone has their nose within 5cm - you yourself may just occasionally discern it for the first couple of hours.
Make sure you haven't caight lice, ensure that you rinse your hair properly to get all the soap out and don't wash it too often as you will dry out your scalp and hair. If it continues despite all that you do, or don't as may be the case, visit your doctor for referral to skin specialist.
An itchy scalp can be due to one of several conditions and it's important to find out what's causing the itch before you can treat it properly. Simply washing your hair too often could be a reason....