Is there a demon around me?

I have a problem with self harm and over a year ago when I started getting better and actually happy something started messing with me in my house. Things from foot steps, unexplainable noises, feeling it on my bed, feel it walk up behind me, and feeling watched constantly. It didn't like my boyfriend. It hit his car when were were leaning against it, hit the inside of his trunk when he was driving away, even saw a figure of a man watch him leave one time. Eventually it all stopped and I had depression problems an selfharm again. Recently I haven't been hurting myself and trying to get better and 2 nights ago the power went out and the darkness scared me and I felt heavily watched. Lastnight I was alone playing minecraft and something touched my shoulder. Is I a demon? Why is it obsessed with me and what does it want? Is it coming back?

Honestly I feel there are demons but that just sounds crazy

Yes.

If you make Jesus Christ your Lord and Saviour, He will give you authority over Satan and all his demons. You will also be saved from eternal torment and inherit the kingdom of God. Do this now:

"Dear Jesus,

I'm a sinner.
I repent of my sins.
Please forgive me and save me by your shed blood;
come into my heart.
I want to receive you as my own personal Lord and savior.

Amen"

You need to plead the blood of Jesus against the demons that are harassing you, bind them and cast them out in the mighty name of the Lord Jesus. Do this and read Psalm 91.

If you were or are involved in any occult activity, this would be the reason for the demonic oppression so you need to immediately repent of these practices and get rid of all occult items.