I have been stuck at the same weight for 4 weeks. Will eating one high carb meal like brownies or toast and jelly jolt my body into losing more?

No
Post here as to what you've been eating, and perhaps we can help you a bit more.
The last thing you want to do is have something so high in sugar. It can cause a long downward spiral. Also, you may be losing the inches and not weight, a phenom we've all gone through. Don't give in to the temptations though.
Like I said, detail a daily menu for us, and perhaps we can catch a culprit in there.
-Chad