I would suggest giving both a good cleaning in the way that Kystar suggested. If the beads were black to start with, you may want to collect some fresh rainwater and run them over the beads, thinking all the while "clouds of black, return to the earth, stars of light, fly to the bead".
Repeating a chant (this one, or something that works better for you) will help to focus your mind. The symbolism is what is important here. For instance, in the chant above, you are cleansing the beads specifically by commanding the "clouds of black" (negative energy or bad dreams that the bead has caught) to return to the earth to be recycled. 'Stars of light" will command what is often referred to as "White light" or "Divine light" , basically Positive Energy to return to the bead to fill in the space that you are clearing. Rainwater or mineral water left to charge in the sun is the best for this, because running water cleans most stones of negative energy that they may be holding onto.
Regardless of which way you clean them, replace the dreamcatcher with reverence. Believe it or not, it is a tool, and as one that you use every night, it will become stronger and better at protecting you if you acknowledge the work that it is doing, even if you don't notice it every night.
As for guides, I think I can help you out there. Unlike our good friend Crazy who is on a first name basis with all hers, my guides are more background figures. Everybody has at least one, and they change as we grow and need different things. The first thing I ever learned about guides is that they can hear you long before you can hear them, and so asking them to guard your sleep, even if you don't know who they are, is a good idea. You may wish to ask them to appear in your nightmares helping you in such a way that empowers you to remove the threat (Ex. - You are stuck in a dark room with something scary that you can't see. Your guide might become a torch allowing you to see that the sound is not a threat). Ask before you go to sleep, and they'll do what they can to help you.
Crazy, feel free to correct me if I've assumed something about guides that you know is too advanced or if I've explained something incorrectly. You're the resident expert on guides. I tend to treat mine like "friends in need" since they only come about and really make their presence known when I need the help. They know I prefer dealing with issues as independently as possible. Fortunately, most of them seem to agree that, for me, this way of "learning" works best.