After 2 years of thinking of joining a gym,i finally have,advice needed

After 2 years of thinking and wanting to join a gym i finally got the courage to join one,the hardest bit was making the first step of just going in and enquiring,so if any one else is thinking of joining one i felt this was the hardest bit

I joined 2 weeks ago,the reason i joined i was gone unfit even though i tryed to think otherwise and i need to lose weight,i was a good bit overweight years ago and i lost it and felt great but as i got older it crept back up a little bit, i went from a 42 in jeans to a 36 but i am now gone back up to a 38

So i got ascesed in the gym and my body fat and bmi are both 32%,so i was given a programe and i have made changes to my diet,my programe was based on going to the gym twice a week as i have a busy schedule but i am an active person anyway,so the programe is twice a week for 50 mins,first cardio on a treadmill for 25 minutes at 5 to 6 km and the leg press 2 sets of 8 at 70 and then the chest press 2 sets of 8 at 20 and then the lat pulldown 2 sets of 8 at 20 again

now after 3 sessions i have increased things alot i am now starting at 6 km on the treadmill for 3 minutes and the going to 8.5 km for 7 minutes up to 10 minutes then back down to 6 for 3 minutes and 10 km for another 7 minutes and then 6 km for the last 5 minutes,still at 70 on the leg press and i am now doing 3 set of 8 on the lat pull down and chest press,2 sets on the chest press at 25 and then one set at 8 and the lat pull down 2 sets of 30 and one set at 35

what are your views on my programe,what would a normal fit person do on a treadmill timewise and speed wise? how long should it take to lower my body fat and bmi and improve my general physical appearance?

sorry about the long post and i welcome your replys,thanks