New magic-user spell: Silverglade's Forcebolt

As a player, I never really paid much attention to the rules in D&D for creating new, unique spells. This is the one exception.

After encountering several situations where I would have liked to have taken advantage of the high damage potential of a Fireball or Lightning Bolt, but found my character (Silverglade Woodshadow) in too small an area to employ one safely, I decided to solve the problem by creating a sort of hybrid single-target spell in the Magic Missile vein. Enjoy!

Silverglade's Forcebolt
Arcane Evocation
Level: Magic-User 3
Range: 100' + 10'/level
Duration: Instantaneous
Components: V, S
Casting Time: 3 segments
Saving Throw: Half

Upon casting this spell, a fist-sized ball of what appears to be pale green fire darts forth from the Magic-User's outstretched hand and unerringly strikes a single target creature or object within range, blossoming into a small (one foot radius) concussive explosion on impact. The target suffers 1d6+1 damage per level of the Magic-User, with a saving throw allowed for half. The extent of damage to inanimate objects is best assessed by the referee on a case-by-case basis (rules for item saving throws may be helpful here; treat as crushing blow). Despite its appearance, this spell is a form of visible telekinetic force, not a true flame.