You are going to run into problems in your meditation. Everybody does. Problems come in all shapes and sizes and the only thing you can be absolutely certain about is that you will have some. The main trick in dealing with obstacles is to adopt the right attitude. Difficulties are an integral part of your practice. They aren't something to be avoided; they are to be used. They provide invaluable opportunities for learning.
The reason we are all stuck in life's mud is that we ceaselessly run from our problems and after our dersires. Meditation provides us with a laboratory situation in which we can examine this syndrome and devise strategies for dealing with it. The various snags and hassles that arise during meditation are grist for the mill. [...]
So don't be surprised when you hit some experience that feels like a brick wall. don't think you are special. All seasoned meditators have had their own brick walls. They come up again and again. Just expect them and be ready to cope. Your ability to cope with trouble depends on your attitude. If you can learn to regard these hassles as opportunities, as chances to develop in your practice, you'll make progress. Your ability to deal with some issue that arises in meditation will carry over into the rest of your life and allow you to smooth out big issues that really bother you. If you try to avoid each piece of nastiness that arises in meditation, you are reinforcing the habit that has already made life seem so unbearable at times.
It is essential to learn to confront the less pleasant aspects of existence. Our job as meditators is to learn to be patient with ourselves, to see ourselves in an unbiased way, complete with all our sorrows and inadequacies. We have to learn to be kind to ourselves. In the long run avoiding unpleasantness is a very unkind thing to do to yourself. Paradoxically, kindness entails confronting unpleasantness when it arises. [...]
When you are having a bad time, examine that experience, observe it mindfully, study the phenomenon and learn its mechanics. The way out of a trap is to study the trap itself, and learn how it is built. You do this by taking the thing apart, piece by piece. The trap can't trap you if it has been taken to pieces. The result is freedom.
--Bhante Gunaratna, From "Mindfulness in Plain English"