How should i go about talking to corporal at police department?

jan 2005 i was dating a guy not knowing him and his roommate did meth on a regular basis then one night i ran away from home when i was 17 and went and stayed with him and his roommate on jan 30th 2005 we were all in the kitchen talking when i had to go pee the bathroom was directly to the right of the kitchen sink and mark was standing in front of the kitchen sink so as i walked in front of him heading to the bathroom he grabbed me from behind and put me in a head lock and started chocking me i some how got away and ran for the front door my boyfriend at the time grabbed me from behind threw me to the floor and grabbed my head and trying snapping my neck it popped three times and then i blacked out and i came to in the living room holding a knife screaming at them. the next day my friend came to pick me up and i told two guys i knew and they confronted them about it and mark and my ex admitted to trying to kill me b/c they were on meth and thought my dad was a cop and that i was a snitch and that they were going to bury me their front yard idk how long they had been talking about it but its scary thinking about it. im lucky to be alive but later that night i was arrested for running away i told the cops what happened and they had me write two statements then while in juvenile detention center the cop who arrested me came in and started cussing at me saying i was lying and that none of it happened. for three months straight i had migranes every single day i would wake up with a migrane go throughout the day with and go to bed with one. i have never been in a car accident i have never done anything before this incident that could have caused this much problems to my neck. three nights ago i went to the emergency room because i had the most severe migrane in my life i could barely move, just walking felt like someone was smashing my head with a boulder. when the dr came in and i told him everything that was going on with me and about how the guys tried snapping my neck he told me he thinks i may have fluid leaking in my brain and that i need an MRI and a lumbar puncture to draw out any fluid. i have an appointment for that but what im wanting to know if i can still press charges for attempted murder i would have done this a long time ago but after being in the juvenile detention center i was placed into geneva-yrtc.the cop that arrested me didnt even allow me to see a doctor, he cussed me out at the detention center, i even gave the names of the two guys that mark and nate (the guys who tried to kill me) tell them what they were going to do to me. how should i confront this situation i have a few main questions i want to ask but what questions would you ask if you were in my situation. and btw this all happened in nebraska. i am calling the corporal tomorrow.