tippmann x7 phenom help please

hey i got a tippmann x7 phenom with a flatline barrel and the x7 phenom barrel adapter that i needed to purchase separately,so i ended  filling up my tank and i bought some p.w.i. smoking dragon paintballs (there size is .68) so when i got home i shot acouple of them and most of them popped in the barrel and the rest were curving all over the place,completely inaccurate,im extremely new to this and dont know exactly what to do now,im guessing it might be the paintballs i bought or the velocity my gun is using,im going to hit the field this sunday so if somebody can help me by then i would really appreciate it thx in advance