Confused about reflux?

I took my daughter to the pediatrician on Monday as she is constantly spitting up her feed. It's probably not all of it but it certainly feels like it. He prescribed Motilium (domperidone) for reflux however it has made no difference and if anything has made her worse. She now cries constantly and seems to have tummy pains and she wants to be fed every hour. The sptting up hasn't stopped so I'm wondering now if it is reflux or could she just be a happy spitter?!? She's only 8 weeks old and is 100% fed. Its not projectile vomiting and before she started on the medicine didn't seem to be in any pain. We've to go back to the pediatrician tomorrow but I just wondered, could it be fast let down instead of reflux because at night theres milk dripping out of my ?? I don't want to worry myself daft with this, if she's just a happy spitter then I'm quite happy washing five babygros a day, at least she wouldn't be taking medication she doesn't need. Just want other mums opinions! Thanks