Aw, poor little one, she does look weak. I'm afraid that the half of large cricket may be very difficult to digest. Baby beardies can eat loads of tiny crickets, but a large one is much too hard to digest. When she shakes her head, did she open her mouth at all ? That is how they vomit....so I really hope that's not what's happening. A vet may not be too helpful, if they are inexperienced they can do more harm than good. If they are truly experienced with beardies, they might help her. Some vets want to give tiny babies shots of this and that, and it can be harmful in a weakened state. She is extremely fragile right now, I can tell from looking at her. If she is impacted, she may need a little vegetable oil, and a warm shallow bath. Try the warm bath, it's different than laying in the water bowl. Just be SURE to hold her head up, and keep the water warm. And get some baby food ASAP. That might help her.