Nags, I’m going to make some guesses here so bear with me. I’ll bet you’re already skinny looking but you have some belly fat or annoying love handles. In an attempt to “get it all off” you are lowering calories and running a lot, watching that scale every day.
You’ve plateaued because your body is likely in emergency mode. You’ve crapped out your metabolism. You may have lost some muscle too, despite the strength gains- that can happen to newbies and young people to an extent. I’ve seen a lot of people (mostly women) get way too thin trying to get rid of that last little bit of fat. Ain’t gonna happen probably, especially if you’ve been overweight in the past. If you do get it all off, you’ll likely feel horrible and look worse if that’s not a natural state for you.
I remember getting down to around 5% bodyfat, looking and feeling like a POW, yet still having a bit of side fat from back when I was overweight. What did I do? I got pissed off and said “Fuck this bone skinny look!” I started focusing on adding muscle. I lost my fear of fat. That was many years ago and now I’m around 208 and have less bodyfat than I did at 159. I’m still not super ripped lean (I have a “four pack”, though) yet I look a hell of a lot better than I did at 159! As the others have said, gaining some calorie eatin’, metabolism boostin’ muscle should be your focus. Just add in some more calories from protein sources, get some good dietary fats, and drop the cardio or at least greatly reduce it. Don’t get in a hurry or you’ll lay on fat, panic, and start going for the super-model-on-heroin look again. (Bad for a women, even worse for a guy like yourself.)
Trust me on this, I’ve been there and so have most of these guys giving you advice on this thread. I probably wouldn’t have believed it myself at your age and in your current situation, but it’s true. Learn from our mistakes. That’s true wisdom.
If you don’t go for that, then at least stop dropping your cals further (actually, you’ve never mentioned cals, so I don’t know how many you’re getting per day.) Try the Delta 1250 diet as outlined in T-mag. Do a search or look at the FAQ section. Next, read the “Diet Manifesto” article. Good luck. I hope you don’t have to learn all this the hard way.