Marrying in NYC in one week and HELP please

[canabby]

Hello dear all members,

I'd like to tell you my situation and ask some questions. I would really appreciate your time and help.

I am non-US citizen and my girl friend is American. We met 3 years ago in Europa and came to New York together 1 year ago. She is working for an NGO and i have aimed to pursue my career in USA. So i had to take some occupational course , in order to study i applied to a school in NY.
My entrance: September 2010. - 6 months B2 tourist visa.
We were planning that i would stay on F-1 visa for 18 months after i complete my studying we would marry.
On February 2011 one month before my I-94 expired, i applied to change of status from B-2 to F-1 (Form I-539)
My B2 tourist visa- I-94 expired on March 25 2011.

Here what happens after that:

On July 24, 2011 I received Form I-797 from USCIS for Requested Evidence. I sent the evidence in a couple of days. Here i made 2 mistakes; i did not add I-797 original notification and i sent via regular post not Fedex or express mail. So i have no tracking number to prove that i sent what i asked.

On October 30. 2011 i received The Denial Letter that says "..It does not appear that you responded within the allowable period of time. Therefore, your petition or application is considered abandoned and is denied.."

After all, we have decided to marry next week, and we are trying to figure out the green card application process,

For now, i have a couple of questions, and i might probably need to ask more later.

-Can we make the application and filling the forms by ourselves or should we hire a lawyer?
-As my I-94 expired on 25 March 2011 (more than 6 months ago), and i was denied for change of status to F-1, Am i in big trouble?
-How long will it take to get a temporary permit for me to start studying at school before i get my green card. Because i really need to start studying as soon as possible.

Any help, comment or add would be really appreciated from whom have knowledge and experience with similar situations like ours.

Thank you so much and all the best.

[immihelp]

Read http://www.immihelp.com/greencard/fa...n-upgrade.html