23 y/o male completely new to lap swimming. Please Help!

So I am currently in college and have always wanted to swim laps in a fitness capacity. Unfortunately for me my high school did not offer a swim team and I was never really exposed to lap swimming. I can swim and have run cross country in high school and long distance events throughout college. That was, until I dislocated my right knee while playing hockey. Since then, I have been seeking an ultra light impact cardio and total body alterternative, ala swimming. Given my relative noobie status to the sport, I have been dealing with many mental hurdles which are preventing me from getting into the pool. These hurdles are: -Pool ettiquete: I don't want to ruffle any feathers. -Where to start my workouts: Swimming isn't an issue. I grew up on a lake and have swam since age 5. I'm sure I'll get my butt handed to me during my first day in the water, but that's what I want. I want it so long as I know I'm going in the right direction. -Solo or in a group: I have rights to a 25 yd pool within my college gym, but we do not have a masters team or college club which also uses this pool. Should I try to make a friend at the pool so we can each push ourselves? *And the question which I'm sure all of you get from us new swimmers, what should I wear to the pool on my first day in order to not look like a complete fool? In the past while swimming relatively long distances, I always struggled with my board shorts falling down my pants. I don't want this at all while swimming my first training laps. Many guys wear either the longer competition suits or Speedos. I'm not afraid to wear a speedo at all. I wear briefs on a daily basis and would welcome wearing speedos while training if they perform better, but if a Speedo is the right suit, should I opt to wear it in the pool day 1? Any help is super appreciated and I really can't wait to join you all in the pool!