my daughter is 8 months old and hates it!!! she now simply rolls back over to her back. she shows no sign if crawling but loves sitting up and can turn all the way around. a lot of babies dont crawl, my brother bum shuffles and i think thats what my daughter is going to do! dont worry about what other people say as long as there doing things like holding toys, rolling over being alert then their fine.
Just be patient!! I didn't start mine on tummy time until she learned to roll over on her own onto her tummy! She hated it before then. Ever since she mastered rolling over, she loves tummy time! she was about 4 months old