That's really great!! hope you do well!!!
I learned jujitsu and bit of karate and judo when I was 8... and I still am glad I did, I was not exactly a macho guy .. and had to go to an all guy school... I am 110% sure that things would be a lot worse if it had not been for that ....
there are few things I would like to point out though ...
an average guy loves to have a fist fight but only when its appropriate ... so in a self defense class ... one must expect to get hurt and be prepared for it...
also please avoid kicking/hitting guys in the groin as far as possible unless the instructor asks to practice them ... trust me it is extremely painful .. especially if you are not used to it ... even then it still hurts like someone just ripped part of your body very painfully out...
most guys would refrain from doing it to another guy ... coz it would just invite that person doing it to get the same treatment from others... and it is called a low blow for several reasons ... one of which is that guys generally do not like seeing another guy getting hit there and will be secretly annoyed at anyone who they see doing that to another guy....

In case if you are looking for books to help you ... I recommend Bruce Tegner's books on martial arts ... old but the best books on martial arts out there...
edit: forgot to mention that Bruce Tegner's complete book of jukado self-defense : judo, karate, aikido (jiu jitsu modernized) is the best among all his books... also the one on judo...
learning a form of self defense is both useful and fun ... so have a blast!!!