The first question is: Do you really like EE? Not just for the money, but do you like it. If so, I am going to make a suggestion I am sure a lot of people are not going to agree, BUT here goes:
I suggest IF...AND ONLY IF you are serious to finish your degree and that you have a strong will and you take your commit/promise to yourself very serious, to take one semester off and continue work. Then you use the time to restudy back the important subjects you missed. The first subject is CALCULUS!
CALCULUS! Start from page ONE, make sure you understand all the mean value, rollie's, limits, fundamental theorem... of the first semester. For the second semester, make sure you study good the methods of integrations, polar coordinates and particular the power series approximation of functions. If you have already studied third semester, make sure you under all the subjects in vector value function, line integral, divergence and stoke's theorems.
Then if you have time, study back the basic circuit theorems and some of the classes you did badly. Calculus is the language of science, pick up any of the advanced division or graduate subjects, they explain in language of calculus and derive all the formulas from calculus. You won't be able to really understand those unless you have a good foundation on Calculus.
The reason I suggested that is because I did the same thing. I hit so many road blocks in studying advanced topics because I don't understand Calculus. I goofed around when I was in college. 4 years ago, I really buttoned down, studying Calculus starting from page ONE! I can assure you if you don't do good in Calculus, you are going to really really have a hard time studying electromagnetic theory in the upper division. Getting "C" in a class pretty much mean you don't quite get the subject. Be honest, unless you are in the top schools, you have to FAIL the class! Been there, done that...no offense.
You are young, time is still on your side. BUT if you do choose this route, you really have to make a strong commitment to yourself to do this and go back to school. I know a lot of people will just slack off and stop going to school...and that will be 10 times worst.
Only do this if you trust your will, that you really commit to go back to school AND you do have the discipline to commit at least 15 to 20 hours a week studying. Yes, this is a strong commitment and only for someone that has a strong will...not for the weak. I did it and I am so happy I did it. I study all the way to PDE on my own putting in 20 to 30 hours week in the last few years.