5 Week Kitten With Protruding Anus, Help!

I adopted a 5 week kitten about 4 days ago, the foster family told me she was just starting to eat solid foods. The first day she she came home only had water, the second day I noticed she had some trouble eating the solid food so I added a bit of water to make it softer. After that I noticed that her poop was very solid and hard. Today we were playing and she ran to hide in my closet when I went to look for her I noticed she had an accident and her little anus was protruding/prolapsed and it looked very red and i think there might have been some blood not really sure. Her anus popped back into place but still looked a bit swollen. I'm not sure if what I did is correct but I grabbed a tiny amount of vaseline on a q-tip and as gently as I could I spread it on top of her anus without pushing or putting too much pressure. 

This is my first kitten, the last cat I had was a bit older so i never encountered this problem before, I considered going to the emergency vet but since her anus went back in to place I decided to ask for help first. 

Maybe she's just too young for solid food and should switch back to kitten formula for a while? Or do I take her to the vet first thing tomorrow morning? 

Any advice would be greatly appreciated! 

First of all, 5 weeks is really too young to be adopted. But you have him now, and should probably be giving it KMR stage 2. You should only feed canned kitten food because it has higher calories than adult food. You can add some water to make it a sort of soupy, or add some of the KMR.  Just like human babies, the kitten needs to gradually work its way up to solid foods (weaning).  Also, for his little anal problem, you need to get some Desitin type stuff for diaper rash, as it is probably painful. Ask the pharmacist for a suggestion. Where did you get such a small kitten from?

My mom actually got her for me, she said it was from a couple who foster kittens for a local cat shelter that's all I know. I knew there was something wrong with feeding her solid food since she's still too small. I'll pick up the KMR and desitin first thing tomorrow morning. Can you recommend a brand for canned kitten food? 

I see people on this site buy the Iams kitten food. But what you want is something that lists meat first. Sometimes the can will say broth or water to process listed as first, and then the meat and that's good because cats need moisture. What you want to stay away from is meat meal, meat by products as first ingredient. Also, no corn, soy or wheat. Rice isn't good either. You could also supplement with Beachnut baby food, as I believe it does not contain onions or garlic. Check label for ingredients. Chicken or turkey, plain, no veggies, no rice.       I'm surprised that a foster family would let the kitten go at such a young age!

I think a vet visit should be done to make sure that since it popped out once, that it doesn't happen again. You could probably put a little vaseline or water based lubricate on her like you would diaper rash ointment but don't use diaper rash ointment. I do agree with the others she's very young to be adopted out. Possibly KMR formula and a little turkey baby food to feed her. Check and be sure the baby food doesn't have any onion or garlic powder in it.