Everyone's experience is different, but there are some problems that many people face when they are learning meditation. Telling you about these problems probably won't stop them happening, but perhaps you'll recognize them more quickly if you know about them in advance. You may also be spared the agony of thinking that you are the only person who has ever experienced these particular outcomes. Some of the most common are:
Feeling that you have to do it perfectly
You sit down to meditate, and it's supposed to be blissful -- instantly -- right? But instead your mind is all over the place, your left knee aches, and there's an unbearable itch in your right ear. Obviously you're not cut out for this meditation lark, and you'd be as well giving up. Remember: if a thing is worth doing, it's worth doing badly. That is not a typo! If a thing is worth doing, it's worth doing badly. Anything that is very rewarding, from parenting, to painting, to meditation, is likely to be very complex. With complex tasks, there is a lot to go wrong, and so you'll make a lot of mistakes. It's natural and inherent in meditation that you will experience a lot of distractions and will sometimes realize that you haven't a clue what you're doing. And that's okay. If you keep doing it, you will learn. You'll learn from your mistakes, and get results that you want rather than results you don't want. I sometimes call Buddhist practice "the fine art of making mistakes," since the point of practice is to pay attention to what you do, learn from it, and keep doing it differently until you do it more to your liking.
Trying to make your mind go blank or chase thoughts (or noises) away
It doesn't work, and it isn't what meditation is about. In meditation, your mind will become calmer and quieter. Sometimes you might even stop thinking using words. But your mind never goes blank (unless you are deeply unconscious -- but then you wouldn't know you'd succeeded, would you?). With outside noises, there is no point in trying to push them away. If you push them away, you are holding on to them. The harder you push, the more deeply entangled you'll get. Instead of trying to push noises away, just let them be there. Allow them to be. Allow them to pass through you unhindered. Let them be part of the meditation practice. If you keep doing the practice, one day you'll realize after meditating that you just hadn't heard them, that you've just tuned them out.
Wanting to "make" something to happen
We may have expectations of what meditation is going to be like, and we may even try to make our expectations happen. We might strive, for example, to experience bliss. Or when we do start to experience some rapture arising, in the form of energy or pleasure arising, we may try to grasp after it and hold onto it, convinced that this is the beginning of some deeply spiritual experience. But what happens is that we kill the developing positive quality as surely as if we'd crushed a small bird in the palm of our hand. Sit loose to your experience. Let it happen. Try to be neither elated or despondent, but maintain as much equanimity as you can. When you notice yourself becoming elated or despondent, realize that these are your responses, and that you can let go of those responses and simply return to the object of concentration.
Keeping a running commentary
"Being aware of" is not the same as "thinking about." We can be aware, for example, of how our body is, without keeping up a running commentary. Try simply to experience. If thoughts arise, don't push them away but also don't encourage them. Instead, just let go of them and let them evaporate. At first you may have to do this over and over again, but eventually the amount of thoughts bubbling up will decrease, and your mind will become calmer. So bear these things in mind as you approach meditation, and remember that you don't have to do it perfectly, and that making your mind go blank isn't the point of meditating. And work on accepting your experience as best you can, while not confusing thinking about something with actually experiencing that thing.