Did I ruin it?

Loiterer

I wanted to make a kensai who could use spells. But I mainly wanted to play as a figher and get up in their grill with big melee damage but could also sling some spells sometimes. But I think I might have done it backwards. I am currently a level 6 mage and I just got to baldur's gate, so I was just starting to realize that I will be locked at whatever spell level forever once I dual class. Was I suppose to go Kensai first THEN mage?

jmerry

As the game only lets you have a kit in your first class (unless you apply mods or other trickery)... yeah, that character's not going to be a kensai. The traditional dual here is to take a fighter (usually with a kit) to 9 or so levels, then dual-class to mage and have high-level spell power in the long run, along with a grandmastered weapon that you can hit enemies with.
Fighter/mages do have their own distinct style, compensating for their lack of armor with powerful combat protection buffs. Played well, it's extraordinarily powerful in the long run.

A mage-fighter dual, as you noted, has a lot of disadvantages. You're limited to low-level spells, and you give up several mage HD for fighter HD. There is, however, one version that works pretty well.
The way to do it? Dual-class as soon as possible, at level 2. Summon a familiar to cover the HP weakness, and go ahead and wear armor. Now you're a fighter who can use wands, scrolls, and other mage-exclusive items. You're slightly disadvantaged for most of BG1 due to the lack of exceptional strength, but the wands make up for it.

Loiterer

Dang it. Looks like I am not dual classing at all. Good to know for next time.

BelegCuthalion

Loiterer wrote: »

Dang it. Looks like I am not dual classing at all. Good to know for next time.

That's a very healthy way to see it - far better than developing a restartitis because of it.