I feel like i'm slowly becoming unstable.

I'll make this short a simple as I can.
I am just going to list my major problems.

- I often have suicidal thoughts, even now. These thoughts include overdosing on medicine, hanging myself, shooting myself in the head, jumping in front of cars/trains, there have even been a few times where I've daydreamed about someone killing me, or even dying from a fatal illness.

- I often daydream about cutting myself, and I have even attempted a few times to cut them. I have also harmed myself in other ways, such as letting blistering hot wash over my hand, and taking more pills of medicine than needed. I also sometimes pick at sores on my legs until they bleed.

- Aside from hurting myself, I have often thought about hurting others in various ways. Examples would be: Punching someone, slapping someone, strangling someone, stabbing someone, I've even thought about raping someone, the thought of someone losing their virginity almost excites me.

- Sometimes, I don't want to physically hurt someone, but rather emotionally harm them. It helps if I know someone and their secrets, I dream about calling them out, throwing insults in their face, making them feel bad about theirselves makes me feel great satisfaction.

- I am very sexually devious. I oftem think about seducing someone, I think about how they will react shocked at first, but then they will give into my advances. This makes me feel powerful, dominate.

- I admit, I have thought about harming and killing small animals, I have never killed any before, but I have daydreamed about killing cats, or rats/mice. I even consider buying a mouse just so that I can take it home and proceed to kill it, maybe even torture it before doing the killing, like shaking it in it's cage, or throwing it against a wall.

*Sigh* I know I'm messed up, and I feel disgusted after reading what I have written above, but I don't know what to do. I want help, but I don't know where to start. Where to go.
I have taken medication for depression, but it never seemed to help, it only made me feel dizzy and sleepy a lot.

What should I do?