3 months out and my weightt loss is slowing??

I am almost 3 months post op, Roux-en-Y GBS, and my weight loss is starting to slow and I'm freaking out.  I've lost nearly 100lbs (95.8), that's great but I have a long way to go, and over the past three weeks my loss has slowed to between 3 and 5 lbs per week where it was 10+.  

I have exercised some but not really strenuously or very regularly to this point and am just now starting to feel like I can.  I will be starting a more strenuous exercise program in two days so hopefully that will help.

I've really come a long way but I'm worried the weight loss has slowed so drastically so soon. I usually eat about the same thing every day.  3 ozs of oatmeal for breakfast, an 8 oz protean shake with 1% milk at around 10 am, then approx 3 ozs of some kind of meat/protean (fish,chicken or turkey) for lunch then approx the same for dinner (probably around 5-600 calories per day.  I'm staying off as many carbs as possible and not really eating many fruits or vegitables at all (really focusing on getting my protean).  I also drink over 60 ozs of water each day.

I just know if I'd eaten this few calories per day before wls I'd be losing weight big time still.  Any advise on giving my metabolism a boost and getting back to 7+ losses each week would be appreciated. 

Thanks

Stalls and slow downs are very common.  In fact you'd be the odd man out if it didn't happen to you.  You've lost a tremendous amount of weight in a very short amount of time.  Your body needs a break and a chance to get readjusted.  Get use to the stalls because from here on out it's going to happen.  One thing that I would recommend is get you measurements now, waist, neck, chest, hips, biceps, thighs, lower legs.  You'll see that even when you're not losing on the scale you're still losing in inches.  It seems like when I'm stalled on the scale that's when I'm going down in clothing sizes.

Keep following your diet instructions, they won't lead you wrong.  Keep exercising, it will not only help to take some of the weight off but more importantly it will help to keep the weight off.  Congratulations on your awesome success thus far.

Duane

Try to remember that your body is not moving around that 100 pounds (great way to go btw) so you are using fewer calories than you did. Five pounds a week is major my friend be very proud. Some times a way to break a stall is to exercise a little differently than before and as strange as it may sound add a few more calories. This may trick your body into thinking it's not starving and release some stored fat. You will need a few good carbs too. 
Hang in there guy you are doing great.
David 

You may want to try up'ing your calorie intake.  500-600 calories is pretty low for a man your size and that can have an adverse effect on your weight loss.  Trying going 800-1000 to shock the system and restart the loss.  Your body eventually adapts to whatever you are giving it and you have to mix it up.  Make sure you are taking in the levels of protein your nut recommended for you as well.

Thank you all for your kind words of encouragement and advise. I appreciate it all and look forward to loosing 100 more lbs. Good luck to you all as well