Because of cost, if you could buy dewormer over the counter tomorrow first thing, it's worth a day or two (providing she will eat, drink, and has energy and doesn't grow worse over the day or two) to see if worms come out. You likely wouldn't see worms, because she hasn't been dewormed. The blood etc from her bottom, again, not a vet here and I'm all about take thy pet to the vet when possible at any cost (unless impossible but that breaks my heart). I'm also a realist and know that some things that could easily rule out something scary, can be done safely provided the pet isn't in a dire situation and you don't wait long to see results and if you don't, get to a vet.
Having said that, I once had a springer spaniel Jake. LOVED that furry beastie. My now ex (easy child's bio father) wasn't a great guy. He refused me going to the vet with Jake when Jake had small rectal bleeding, problems with bowels. I was horrified. I was helpless, he controlled all money at that time. I had no power to go to a vet. A couple up the road greeted us from their porch twice a day and loved my dog. They said hi on a walk by and asked how Jake was, I burst into sobs, having just had a blowout fight and stormed out for the walk, over the topic of the desperate need for the vet. They were all over me, asking what is wrong, I explained my problem. I mentioned I may have to give the dog to the humane society just so that a vet can treat, but it's cruel for my dog to not see a vet. They offered, because they worshiped my dog, to adopt him and take him to a vet. One last night home, and I surrendered him to them for his medical needs to get met. Worst day ever. Avoided their house for weeks out of heart ache. They prance by one night with my loved Jake happy as heck. I ask how it turned out. It was a in/out appointment at the vet. A simple allergy to his food. Switched food, problem GONE. Gosh if anybody had even suggested it I'd have tried it and still had my beautiful pet. Perhaps while waiting a day or two for dewormer to kick in, try changing kitties food. Remember so young, their bodies don't always handle real food well yet and aren't experienced with what makes them sick or not (Well, you the owner I mean). It can't hurt to try, maybe your little manx buddy will end up all well and good, without the vet.