Can any one explain me why i am loosing more xp in chalnges more than 15 xp when i lost and getting less than 10 xp when i won ?

Question

regrading chalnges ...

Answer 1

✓win challenges using different different weapons, and not stick to one for a long time since experience you earn lessens with each challenge you win with the same weapon.
For example
*do 5-6 challenges with one
*then do 5-6 challenges with another

You can also go so low as 1XP for winning a challenge,
ps.It happened with me using java

Hope this helps,

Answer 2

thankx @kisuke urahara.