I agree with Lulu, it sounds like she still has some wind. Try lying her on your knees with her head slightly below her tummy (after a feed) and pat her back. After 10 - 15 seconds. lift her upright and rub her back upwards. That is often a good technique for bringing up trapped wind. I also second the suggestion of a sling. Holding your baby is what nature intended you to do, and tbh it's perfectly ok for you to just sit with her all day if that is what makes you and she happy.