This is very tough for any of us to answer because it could be a number of factors. Women tend to have more knee issues than men because of our wider Q (quadricep) angle--the angle from our hip to our knee. But other factors include poor firing of the glutes, weak hip flexors, tight hamstrings, tight lower back muscles, even the running surface you are running on. As one of the posters mentioned even your shoes. But it could also be the longer mileage and your body has yet to adapt to the increased distance.
If you are in pain, I do not recommend that you run again until you are pain free for a week and then slowly build back up. While I have no problems with KT tape or Rock tape, you should NEVER use it unless you have been shown how to apply perferably by a physcial therapist or sports chiropractor. Using the tape in a way that is not meant for you, may actually create other issues up and down the kinetic chain.
Remember it can take a solid year of consistent running for your muscles, bones and connective tissue to adapt to the rigors of running. And as you read in the first paragraph, lots of potential issues can lead to knee issues which have nothing to do with our knees at all.