should I be worried?

Question
I currently have two snakes both females one is almost 2 years and the other is about two months. The baby seems to have trouble digesting, we have had her about a month. We have fed her once but she is so little she had difficulties killing it, so after about an hour of supervising her first feeding my boyfriend flicked the mouse in the head to kill it, i guess she wasn't strong enough to constrict it. When she struck at the mouse first she missed the head and went for the ass. It took her a long time to digest and shed. Her end was swollen, and then after 2 weeks of finally starting to shed she also digested but it was diarrhea. Today she has shed completely. We fed her again about 3 days ago and her butt seems to have swollen a little again. We fed her pinkies so i don't think were over feeding her. Is this normal? I read online that if you can see in between the scales of your snake that could be a sign of obesity but then again shes just a baby only 9 inch! So I hope some of these concerns are just me being a worry wort, but I have also noticed that she has some abnormal posture sometimes, when ever i hold Lucy (my older snake) she never lays to were her tummy is facing up but Bella, the little one, is always twisting up in weird ways were it kinda concerns me its really hard to describe it i hope I am giving you enough detail to were you can help me. So now back to Lucy, shes been in a bad state were she escaped and was outside for a while but she doesn't have any mites just roughed up scales, and she does make this noise like a sniffing noise when she breaths, but it only happens every now and then is this something i should be concerned about?
i apologies for long and what seems like dragged out concern but if you or anyone can give me some good advice and reassurance that would be great!

Answer
Hi Marissa,
  I would not be concerned about the little one. As long as she is eating and passing food, she should be fine. One thing though, small snake are prone to death for a million reasons, so do keep a close eye on her. The older snake sounds like she might have a respiratory infection. Does she have any mucus in her mouth or excess saliva? Is she gaping her mouth to breath? IF so, then raise the ambient temperature a bit and get her to an exotic animal vet.