22 male and 24 year old woman isn't an older relationship. Older relationship would be where the woman was 38 you're 27 and her 14 year old son loved throwing hammers at walls when he was beat on xbox games by his 11 year old brother.
When you enter into ANY relation where kids are involved (not your own) you've got to be able to handle shit you've never experienced before. It could be crying for mummy temper tantrums the terrible twos or wanting all of mummys attention and the occasional violent outburst when they don't get it.
You both have to clarify boundaries and what fun actually entails, theres fuck all fun about being kicked out of McDonalds as a treat for a shopping trip that passed off without much turmoil until the eldest threw a huge ADHD hissy while we're having burgers.
Seriously run away flee for your sanity now!