Problem with Misdemeanor citation

[AgentDuo]

What is the name of your state?What is the name of your state?NE

So after driving my little brother home from work at 12:30 at night, Diana (my german friend who came to visit my roommate) mentions something about the missourri river. So I figure, thats fine I'll show it to her, so we drive by and get closer to Dodge Park and she mentions she can't see it. Well I figure we'll go into Dodge Park real quick to the docks and just take a look. So I pull into the park, and just before we get not even halfway down the road my other roomy in the car says "I think parks close at 11" (this is about 1a.m.") so I am like.. I think your right, so I go to turn around and leave and when I do I then see another car coming down the road the other car starts to slow and I slow then they stop and on come the lights. So immediately I shut off the car, and sit there. The cop pulls up and gets out, and starts asking for my info, not even a minute later ANOTHER cop car speeds down the road and squeals into the lot and almost hits my car. They get out and start asking the other two for their information. This is all a little crazy for me because I have never been pulled over or gotten a ticket or anything. One of the officers ask for my german friend for her info and I say "She is from Germany she doesnt have any" and the lady cop says "Oh good your friends brought you here to get arrested" Which I felt was totally rude and inappropriate. So we go through all that, then the lady cop just drives off. One of the other officers asks me to step out, so I go up and talk to him "Anything you want to tell me before I start writing tickets? I say "no" he then says "Do you have an relations on the force?" I then think "yeah I know of an Officer Bonacci, but I dont know of his relationship" so I say "No" and I go sit in my car. After sitting there for 15-20 minutes they search us, and then proceed to search the car. Then they call us over to the front of the cruiser and say "We arent booking you tonight, but this is a misdameanor so you will have a court date" I look at him and say "Isnt this just a fine or something?" and he proceeds to tell me its an arrest without booking us. That really surprised the ever-living-beegeebus out of me. They left Diana out of the report because she could get deported, which was a reliefe,but I figured at the least it was a ticket or a warning. I didnt have any drugs or anything illegal and in all actuality I wasnt even halfway into the park before I turned around. So now I have a court date, and I have no clue what I'll get but apparentely I can take some class to get it cleared up. With any luck, the whole thing will just blow over, maybe the judge will be nice. The officers never even bothered to ask what we were doing there.

So heres the questions;
How do you think I should plead? No contest I still have to pay a fine and then take a class to get it off my record.
If I contest it, I have no clue how that works, do I get a lawyer?
They also searched my car, which they did not ask for permission to do, while I would have given permission, as I said I was in the park for a whole minute if not less and they must of followed me down the road more or less, so they knew how long i was in there as well.
I never even got a chance to say what I was doing or the fact that I just plain forgot the park was closed. I was just asked a few questions. I had no clue what to do at the time and am still confused. Any help would be appreciated.

[outonbail]

Are there signs at the entrance to this park which advise of it's closing time? If so, (and I imagine there are) your probably screwed.

If the signs were damaged or not in place at the entrance you entered through, or you weren't from the area you may stand a chance at getting it dismissed.

Did they just cite you (the driver) or everyone in your vehicle?

What was the exact charge or code violation you were cited under?

[AgentDuo]

There is one sign at the front, its a really small sign, which I did not see. (probably the size of a normal no parking sign) They cited Andy and I but not the foreign gal because she could of gotten deported. They didnt even include her in the report. My problem is that honestly I forgot, and I was turning around to leave, also I was in there for less than a minute. we never stopped the car, never got out of the car.
Also they never asked to search the car, now I'm aware that with probable cause they can do it, but I never was even asked if they could, they just searched us and then started searching the car.

I was cited under statute 21-1.

I'm seriously contemplating pleading not guilty because like I said honest mistake, and was never asked for any explanation or for permission to search my vehicle.