will this ever go away?!

Don't take yourself so seriously. We all have slip-ups once in a while when we are in a negative state of mind. The important thing is to learn from them, and make a plan of action on how to prevent them from happening in the future.
Cutting is an expression of depression or anxiety; a way of showing others that you are fearful of yourself or your life. And some find a sense of relief in it. But the truth is, this is only a big deal if you let it be. Don't dig yourself a deeper hole by feeling guilty or ashamed. No one judges you. Not God, not anyone. As I said, we all slip up once in a while. And the feelings of depression and anxiety or confusion can be improved before they get worse.
You need to identify why you are feeling upset and decide how you're going to take control of it. If a certain thought doesn't make you feel good, choose another! It really is as simple as that. You just need to learn how to control your thoughts. They are meant to motivate you, to inspire you, to create with, to make you feel good. If they aren't doing that, you aren't thinking the right thoughts.
Start now to turn this around. It's all up to you.

I think it will heal fine and go away, you might have a light pink mark where the cut is.

I'm sorry you feel so down, and you felt the need to do this. It's sad when anyone feels invisible. I don't really know what could help you, besides learning from it, I suppose. Try to find reasons to be happy, and turn to the people you know will always love you. I would suggest going for a walk in the sunshine, take music or something, and just be alone. You're perfect because you're you, and always will be.

I cut myself with scissors. It broke skin but hardly and, it didn't scar so I doubt yours will either, and I felt HORRIBLE. And I realized that if you feel like crap after, then obviously that's not the approach to your problems, not saying that it ever is but you get my point I hope.
Just let it heal, I wouldn't tell anyone about it but if your having problems, talk to someone to get it off your chest :)

It will. Sometimes cuts take longer to heal for different people, but they WILL go away if it's not deep. I had a cut like that, with a razor not a needle, and it only took a few months to go away, so you should be good. Just cover it with band - aids until then, and come up with some stupid excuse.

It most likely will not scar.

I don't want to become too personal or detailed here but if you would like support or a friend to talk to, please feel free to email me at okcupidgirl@yahoo.com

Personal experience with cutting, depression, anxiety, and bipolar disorder

The cut will heal if it's small like you said than it shouldn't scar up so u should b fine.
Also don't let other people tell u what to do the only person that can change u is u don't let anyone make ur decisions.

no offense BUT WTF were u thinking lol and yes trust me it will go away for sure lol when i was a kid i poked myself bunch of times dont worry was there blood?