I had it.  I got a deer tick on me, and lo and behold, two days later a bullseye rash.  I went to the doctor.  they tested me for lyme disease and I came up negative.  then they told me that tests don't always work.  I told them to give me the antibiotics now before it got worse.
the crazy thing is I actually had to work hard to convince the nurse to give me a prescription.  my point was, better safe than sorry.  seems pretty reasonable to me.
I didn't want to go through what my friend went through at beach week.  he was lying on a couch saying in his southern accent "guys, I'm really sick!  I need to go to a hospital!" but we all just thought it was alcohol related and told him to sleep it off.  I still feel bad about that.  when he got home he found out the bad news.  he's fine now though.