Analysing an attitude scale

Basically Iam doing a project looking at non student drinking attitudes (previous research about students being heavy drinkers) Basically I have 30 participants to fill out a likert type scale on drinking behaviours and my main aim is to see if their are differences between gender and also the two age groups (18-24 and 25-30). My main hypothesis are that males will be more heavy drinkers than females, the younger age group will be heavier drinkers than the older age group but I am also looking to see if participants see their friends as being more heavier drinkers eg do participants underestimate their drinking but over estimate their friends drinking. I have attached the questionnaire and as you can guess stats is not my strong point but I need help on how to analyse the data. First the likert part of the questionnaire i have been told a t test but there is also a question asking how much they drunk (i worked out units) and how many units they thought they had drunk) so need to see if they underestimate/overestimate their drinking. any help would be appreciated:confused: