Keep those verb tenses the same:
What I did take pleasure in
is was being with friends and going out.
Hmm... This is not exactly a complete sentence. Also, it seems a little abruptly introduced into the paragraph. How about:
"Through college, I can pursue the jobs that I truly enjoy."
Here, it is possible to do something that is closer to the originally intended meaning... like:
Personal satisfaction will come with entering a field of my choice rather than just having a job.
This is a good place for a semi-colon:
It has taken me eighteen years to attend college but I do not regret it; instead I am embracing it.
Talk a little about the career you are entering! Good luck...