Funny story, I was in almost your exact position.
I too was in Philly for college at age 19/20 5'11.5' (so close) and weighed in at 255-260 lbs when I was 20 a few years ago. I started going to the gym and things on a very very INconsistent basis and it never did anything. Once I finished my freshman year of college, after gaining the freshman 15 (or 30 YIKES) I started running/exercising. It started on the elliptical since that was easiest for me at the time since I couldn't do the treadmill for more than 5 minutes without being extremely out of breath at any jogging pace. In the end, I lost 60 lbs in a year.
My "program" was ellipticaling for 35 mins 4-5 times a week. As far as eating goes just develop a schedule. If you have a job, pack your lunch, plan ahead, know whats for dinner, make smart choices when you are on the go.
As far as your workout plan is concerned I think that is overkill and you will end up burning out quickly. This is just my opinion and by no means am I a personal trainer (I am still battling with a kind of yo-yo weight loss...went back up 20 lbs and just recently lost it again, back down to 200 looking for 180) but yeah, start slower. Do 35-45 mins of cardio, push yourself but don't kill yourself. Again, this worked for me. As far as the time frame goes, it will be incredibly tight to lose 50-70 lbs by march, I generally go by the rule of about 10lbs/mo and that is pushing the "healthy" limit. so we 5 months from now...
Just keep with it, make smart choices and fill us in on your progress whenever you want!
GOOD LUCK!