It sounds like you learned to knit more or less the same way I did, only I did it with looking at two needles, some yarn, and a peice of knitted fabric. If you're knitting into the back of the loop, you might have taught yourself "combined knitting" which knits into the back of the loop, and purls into the front, untwisting the stitches. Look at the knit side of the fabric you produce. If the bottom of the v's isn't crossed, that's probably what your doing.
The most important question to ask yourself is do you like the fabric you end up with. If not, look into knitting techniques until you get something you do like. If you do, and you're comfortable with the knitting style, why bother changing it? The one sort of tricky thing about combination knitting is that decreases slant the opposite direction that they do for traditional style knitters, but it just means that you'll need to learn what decreases do what and how to read patterns for what they mean, rather than blindly following them to the finished peice, which I think everyone would agree is a useful skill that you'll have to learn eventually if you want to be a good knitter.
~Emily
I was doing combined knitting with no problems until I wanted to do lace work. I didn't even know I was knitting wrong until I tried a pattern and my slip-knit pass and my knit 2 together didn't look like the picture. Then I had to figure out how to make my stitches lean the other way. Eventually I figured out how to knit properly and I am a knitting fiend now. Even if you could just go to one class to learn how to do the basic stitches you could practice your tension on your own. It is much easier to just learn the right way than trying to unlearn the wrong way.
So now I knit the proper way most of the time unless I am doing something that is straight stockinette.