I don't think we have enough info with the little that you've told us to know if it's sensory or something else (could be vision, could be social anxiety, could be not understanding how to relate to the other children, could be introvertedness, could be a ton of different things). I think that what I'd do if it were my dd is to pay attention to how she acts around children in different settings - is she interacting with children on the playground or during project work at school? What does her teacher say? When your dd says she doesn't like to have too many people around her, is she ok with that or does she seem worried about not wanting people around her? Has she made friends at her new school?
Unless you've seen other signs of sensory issues I wouldn't necessarily think this was sensory.
Best wishes,
polarbear
