This story is pretty embarrassing but I'm going to go ahead and share it...
I'll be the first to admit that I know next to nothing about bike maintenance and repair.
On Saturday evening I checked my tires and decided that it would probably be worth it to add a bit more air. However, instead of adding air, I managed to let all of the air out of my back tire. Then when I tried to reinflate it, the tube didn't seem to be taking air. I checked the valve and noticed that it seemed to be broken. My tires have presta valves and the piece that you unscrew wouldn't stay unscrewed at the top. Instead it seemed to be collapsing down on itself. Of course, I immediately panicked.
I called my brother, the only person I could think to call that knew something about bikes, and he confirmed my suspicions that I probably needed to replace the tube. It was during this conversation that I checked the tire repair kit attached to my bike and realized that I had no spare tube. As background, when I got my bike from my friend in January I took it in for a tune-up. I told them that I knew nothing about bikes, but figured I needed to purchase a basic kit in case I got a flat. I purchased the one that the employee recommended and I was told that it could be installed during the tune-up. To be honest, I can't remember if there was any conversation about the spare tube that I would also need to purchase, but I guess I just assumed that I had purchased one of those as well. Apparently, I had not. I also had not thought to check out the contents of the kit until this very moment.
My brother said he had a spare tube at his apartment, but that he couldn't be sure it was the right size and that if I could go buy one, that was probably the best idea. At this point it was about 7:45 pm. I realized that the bike shop near my apartment might close at 8:00 so I hung up with my brother, sprinted to my car and drove over there. Sadly, it had closed at 6:00. So, I called my brother back and he said that if I could pick him from the party he was currently attending and drive to his apartment, he could get his spare tube and come back to my place and help me install it. So I picked him (and his girlfriend) up at the party in Arlington, drove into DC to go to his apartment and then came back to my apartment.
It appeared that his spare tube might be slightly too large for my tire, but we decided to go through the whole process because we thought it still might work. I got a crash course in removing the back tire on my bike and how to replace a flat tire/tube. However, as soon as we put some air in the tube it was clear that it was too big. There was no way that we could have put the tire back on.
Although my brother had asked me if I was sure that my original tube wasn't taking air and I said I was (pretty) sure, at this point he tested it and it did seem to be taking and holding air (thus confirming that I am completely clueless when it comes to all things bike related). So, we reinstalled the original tube and were able to fill it and put the wheel back on. And yes, I was totally embarrassed and apologetic about the whole situation. Fortunately, they were good sports about it and I returned them to the party that was still in progress!
When I got back to my apartment I noticed that my wheel was now rubbing against one side of the frame. I was kicking myself for not noticing this before he left, but somehow I realized that it was probably screwed in too tightly on the side. I was able to make the necessary adjustments and get it centered and spinning freely. A small win that made me feel slightly better about myself and my abilities to approach problems logically and rationally. (I also may have texted my brother again in a panic, but had managed to figure out what to do by the time he got back to me suggesting the same strategy).
By the time all of this had wrapped up it was around 10:00pm and after all the (self-generated) drama, there was no way I was going to fall asleep right away. So much for my planned 9:00pm bedtime before a 4:00am wake up call.