I've been playing guitar for about 3 or 4 year, self taught with the help of some very useful and notable websites. However, I've recently decided to take lessons to tighten up on some things and advance in the areas I couldn't teach myself...but I have no idea what to expect and if everything I've ever did will be wrong, and I'm a little nervous about it.

My real question is that if you are self taught, are your skills automatically worse than those who have been taking actual lessons ?
Someone who is self-taught may not have worse skills than someone who took lessons, but chances are, the person who took lessons will likely have better form and technique.
I have had several students like you. A good teacher can really help you develop exponentially faster if you're willing to do the footwork.

Typically, self taught students tend to have a sloppier instrument hand. This doesn't make them worse than other students, as both self taught players and students come in all different levels.

Overall, if you can get a good teacher, I would highly recommend it.
Personally I'd been self taught for a year and a half while my current rhythm guitarist had been taking lessons for 7 years and I was miles ahead of him in everything, so no, taking lessons doesn't mean you're automatically better than someone who hasn't been taking lessons.

^ Add that to what those two guys said