First off, you would do yourself well to buy some onyx and carry it with you EVERYWHERE. Possibly even get it as a necklace. Ebay is pretty cheap and efficient with these sorts of things. Clear them by setting them in full sunlight for a full day right when you get them. Try not to touch them, the last owner could have left negative energies on there, you do not want them to connect with you. Clear them about once every two weeks if possible. As well as buying more red clothing, it helps reflect off negative energies. With the dreams, I honestly do not know what to tell you. This happens to me as well, but slightly different. I dream of something happening, not nesecarrily big or exciting and it happens. But normally only with my family and something that involves me. This is called precognition. It does not effect me as much as it does you, so I do not know what to do to control it. Sorry. Try protecting yourself when you are in public, imagine yourself in a ball of white light, very bright, it helps. I have a list of stones that I will send to you in a message as soon as I find them in my documents!
Hope this helped! -Kaitlyn