Hi there! Congrats on your initial loss, and don't worry about the "stall." It is VERY common to "stall" after the initial drop in weight. Your body needs time to readjust.
Look at it this way. The first big loss is water, plain and simple. Your body then equalizes and tries to get back to a status quo. It does this by replacing the fat that is in your cells with water. That's why there's no pound loss. You probably will, however, lose inches. When your body "realizes" that you're going to keep eating this way, it will drop the water, usually in a whoosh.
I lost a measly 6 pounds on Atkins Induction, and then "stalled" for more than 2 months. Not a single pound more lost. However, a pair of slacks that wouldn't even budge over my hips when I started slid right up and zipped with no problem at the end of that "stall."
Ya gotta give it time.
As for the workouts getting harder, are you taking potassium and magnesium? You really should. LC eating has a strong diuretic effect on your body, and when you pee a lot you lose these vital minerals. You really must replace them.
I take 2 tablets of potassium in the morning and 2 more in the evening. If I don't, I get leg cramps and restless legs at night. The magnesium has loads of health benefits, one of the most noticeable being that it helps relieve constipation. Start out with 1 or 2 morning and evening. Keep it up for about a week, and you'll be glad you did. To get things "moving" I had to take 2 in the morning and 2 in the evening for quite a few days, and then was able to taper off a little. I still take at least 1 am and 1 pm.
Oh, I'd also cut back a little on the salty snacks, even if you're drinking a lot of water.
At least that's my opinion!