Am I lifting enough to see a difference?

are you eating at a deficit or surplus?

The sets and reps are great, but the order is all messed up. For starters, it's weights first, then cardio.

As a general rule you want to start with compound exercises like the presses, and then do isolation moves for the muscles in the previous compound move, i.e. follow your flat bench press with chest flyes, follow your rows and pull downs with the back flyes.
If you're going to do only one leg move, I'd make it a full body one such as squat or dead lifts if possible.

You're obviously doing enough to build muscle, as you're causing fatigue. Make sure your nutrition's spot on, and your sleep. Not being able to repeat the same weights is an example of overtraining. You've not recovered, you could do some very light weights to improve circulation and recovery, but I think you'd be better off with a different training split. By turning your one workout into two, you could add some more exercises, but ultimately give each muscle group enough time to recover, without having to go to the gym less often.

While it should work, I see a lot of isolation exercises in that routine. I would suggest sticking with compound exercises like squat, bench press, overhead press, dead lift, and bent-over rows. The stronglifts 5x5 is a great routine to build strength using those exercises. Isolation exercises have their place, but you would be better served by building a strong foundation first. You can find the stronglifts report which will explain it more completely here http://stronglifts.com/free-stronglifts-5x5-report/

I also suggest doing the weights before the cardio. You want to have as much energy as you can to do the weights, not to mention the mental clarity.

OP,

What are your goals? Are you trying to gain muscle and bulk right now or are you trying to cut down bodyfat first while retaining as much lean mass as possible?

Also when you are starting out with weight training, you should start by doing compound lifts moreso than isolation exercises. Niner and a few others in this thread have it correct.

In my opinion, you would do well to start off with full body routines 3x a week (Mon, Wed, Fri) with these exercises:

Barbell Flat Bench
Overhead Military Press
Barbell Curls
Bent over Barbell Rows
Full body Squats
Deadlifts
Calf Raises

Done. You should probably do this kind of workout 3 times a week for ATLEAST 6 months to a year before you even start thinking about anything else.

You have a combination of push and pull exercises listed. You don't really say exactly how much weight (heavy or light) on each you are using to fully exhaust your target muscles.

From my experience, here is what I recommend:

build a routine based on the number of days you lift. if you can seperate push from pull exercises, that will give you very good isolation. Bodybuilding.com is a site I use frequently for this advice, along with my gym fitness guy/gal.

High reps (12-15, 20 max over 3 sets), low weight tends to tone. High weight, low reps (5-8, over 3+ sets) tend to build muscle. What do you want to do? Me, I want gains, not focused on my body weight but rather my endurance and strength so I push hard, low reps when needed.