3 month old crying after bottle

[nwlv]

I have a 3 month old and she was drinking 6oz every 3 hours but sleeping a 6-8 hour stretch at night

She started crying at the end of 6oz so I upped it to 7oz but she doesn’t seem to be able to keep 7 down and she has a lot of spit up afterwards and belly ache

I’ve also had the odd bottle where she drains 7 and still cries but I don’t want to give her more if she can’t handle 7

Anyone have any ideas?

My 3 month old is the same. 7oz every 3 hours and sleeps 6-8 hours at night. He keeps crying after about half his feeds as if he wants more but is sick so obviously doesn't have the space for it. Only thing I've found that helps is waiting 10-15 minutes in case he's eaten too fast and not realised he's full, then rocking him til he naps it off for half an hour. Hope for both of us someone else comes along with better advice!