Why am I killing (almost) everyone with one hit?

[Modern]

Ok, so I've been playing for the first time in a while, and I'm killing most enemies in a single hit, which feels really cheesy, so I suspect there may be an issue.

I'm on Normal difficulty, using the spell "Weak Fireball" and I'm level 5. I'm blitzing the Mage storyline, and most enemies (especially the humans) get killed by a single Weak Fireball. Not everyone does, the creatures that use fire magic take several hits still.

Is it just me, or is this normal? Yes, increasing the difficulty would help, I know that.

[JavaJack]

That seems odd. Maybe you just made a really good mage build? you know, high elf, good skills, etc? It seems odd that you are doing that much damage though.

[Modern]

So it turns out I, uh... sorta did change the difficulty because I thought the slider was the sensitivity bar, for some reason. Whoops. Also, I'm a Breton with <50 Destruction.

[CullinB]

I made test with my Lv3 High Elf Mage just now with Setting Normal(50/50).
This mage character is around 50 Destruction skill.
She took 5 or 6 weak fireball shot to beat her enemy (Mage Guild Story line Enemy in Skingrad)

[Doc Scratch]

In 10 levels, you will be throwing your computer because a rat one-hit you.

[Modern]

I went up maybe 5 levels and I hit a kind of a brick wall. During the part where one of the Mage guild houses is on fire, the skeletons in the basement were giving me the business. I had to get some new spells before I could take 'em.