Players must not use or attempt to use any cheats or errors which they may find in our software. Any exploits a player finds must be immediately reported to Jagex through Customer Support.
Why we have this rule.
We put a lot of effort into balancing our games to make them as fair and fun as possible. Bugs can spoil the effect of a game, so we obviously want to fix them as quickly as possible. Deliberately taking advantage of a bug can unbalance the game and devalue other players' efforts.
Taken from the Rules.
If Jagex caught you cheating as you claim, then you are very lucky they have not just banned the account outright. Many many people who abuse bugs no longer have their accounts.
You have been lucky to have have a few exp wiped off the account.