Hi TK,
Sometimes (most times) our own hunches are the answer to our question. Yes, too much exercise can slow weight loss, but this may not mean you're not losing fat. You may just be replacing it with muscle.
Are your pants falling off?....
That could be a sign you're still losing flabbage.
Give us sample of your daily eating and activity schedule, and maybe we can see something that may be causing probs.
Of course you're drinking all your water?
Any stress right now or meds?