Will I be ready?

I want to run the Music City Half Marathon in April. I went for a run for the first time in a looooooong time. We're talking a little over a year people. See, I used to be fit. I used to run 5ks. But then, I cut my foot, and I met LC. All that went down the drain. I've always been a walker/runner. In college, I did it to stay in shape truthfully? I did it to work off all the alcohol I drank the night before and maintain the weight I was at without watching anything I ate. For awhile now, I have been feeling sluggish and tired. I know what the problem is. Before you even ask, yes, I take a multi-vitamin everyday along with Vitamin C. It's because I'm not active. I don't work out. This is the second time in my life that I gone more than a year without running. And just like the last time, I feel tired ALL THE TIME.
Last night, I went to take Puggy to the bathroom when I got home. All of the sudden, it just hit me. I just started to run. I ran, and I ran. I ran for a mile. That was all I could do. It's official. I'm a OUT OF SHAPE. I plan on getting into the groove again. I feel so much better today. I'm tired, but that's because I stayed up til almost midnight. It's a different kind of tired. Not sluggish, out of energy, tired, but didn't get enough sleep tired. For once, I feel better. I have more energy than normal even though I'm tired. I had totally forgot why I loved running in the first place. So, I'm in my place again. My friends are talking about running the Music City Half Marathon in April in Nashville. I want to do it. However, I'm not sure if I'll be ready, fit-wise, by then. I can barely run a mile now, and it only gives me 4 months to train. My friend Southern Domestic Diva sent me a website for training. I think since I'm so out of shape that I will start with the 8 week 5k training, and then for the last two months do the hlaf training. Thoughts??? Have any of y'all decided to this before? Suggestions are welcome!