My baby is 3 Months Old and 10 lb now he was born early at 37 weeks at 4lb 13 oz and HATES tummy time he will lay for about 30 seconds then Start fussing and crying then screams buddy murder he really likes to sit up and play or jump in his bouncer so laying their on his mat he is very un happy he won’t lay on his stomach or back no matter how many toy attachments I get he isn’t having it so my question is how important is tummy time ?