Gastro bug and sore tummy still 2 days later

So Ds had a tummy ache Sunday morning that then went away all day until the arvo when started complaining again major then about 5 pm did a big vomit well he only did one more about half hour later and that was it but he was awake all Sunday night doubling over crying my tummy my tummy sa sore so I just thought it was the bug then I started diarehoa(sorry if tmi)bad Monday morning felt queasy all day but didn't vomit until late Monday arvo then I vomited again(identical to him)but I've had quite a bit of diarehoa where he's had none,my question is he's still now complaining pretty much 2 days after that his tummy so sore and I mean all day!i thought we both had the same bug but my tummy a fine now in less time so I'm just worried anyone had this?could it be a bug still or should I take him to doctor?hes fine in himself just Cary's out every few minutes but there's no more vomit ???please help anyone?hes not a winged boy usually if he winged its something wrong