Is it a dairy allergy ?

I've really red cheeks and iv seen that this can be a symptom of a food allergy , I'm cutting out dairy for 2weeks as a test but I'm finding it really hard to find foods with no milk in them so far today I had grapes a banana and these breakfast biscuits but they have semi skimmed milk powder in them but I don't think there's much will this affect my test or is it just actual milk, cream, butter yoghurt and cheese I have to cut out ? I'm a 17 year old female. Thanks :)