Your mind is both a beacon and an antenna; you're really a multidimensional being that's restrained in a 3 dimensional container. For most, your 3 dimensional senses are all you've ever known, yet now and then your other senses will trigger - it's like not all of your multidimensional being quite fits into your current physical being; it's never a 100% fit. The reality is that we are all in a mental, thought-based universe; the 'physical' is an illusion, as are your five senses.

When you meditate, you open your inner-self up. You're releasing more and more of your real being, from the physical being. Your 5 senses are fading away and your real senses are taking over. This is normal. This is why meditators work at minimizing distractions, being absolutely relaxed and calming the mind. The 5 senses have to fade for the mind to expand.

In opening yourself up, you'll attract both positive and negative beings. If your inner nature is upset at what it senses as negative, focus your mind on informing that energy to stay away. This is no different then when you walk around your neighborhood and you advise someone you're not interested in communicating with them for whatever reason. As a spirit, you have the same rights. Your energy is your own; you have a right to open or close the door to the energies you choose.

So what if the negative energy doesn't leave you alone? Be absolutely strong with your mind. Reinforce the intent to leave you alone. All of us have guides; those that are tasked to watch over and assist us on our path. Call your guide to assist. Call their guide to assist. Both will assist you, and that energy.

Negative energies are not 'evil' per se, they're energies like all of us, only they're lost or afraid of returning home. There are also dimensions that overlap our own, that from time to time will resonate with ours, observable when we meditate. Somehow you and that negative energy are in sympathetic resonance. Your guide is always watching over you; always listening and ready to help and where necessary, teach and protect you. You're never alone. Your soul group, a cluster of friends that you know is also with you and within reach.

Don't fear the energy or entering a meditative state; call your guide to keep any negative energies away. Take time to know what you want out of meditation - do you want to learn something, or heal yourself etc? By knowing what you want, your energy will resonate in that direction and your mind will focus. If you meditate without some plan, you'll attract both positive and negative energies.

Hope this helps.