I don't know if this is normal or not... Today my Challenge Help XP got to over 400xp, for each challenge I did it slowly got higher and higher which is the effect I was expecting. Then it changed direction. For EACH challenge help I did, it would reduce by about 15xp... so from 291 down to 275xp. I have never seen it decrease as you do more Challenge Helps. Is this what should happen or is this a bug?