Your bike is fine. Only replace what you break. When I got back into riding, I went and bought a Redline Column. It was 22 lbs, and honestly, felt way too light, and I didn't like the feel of it at all. So I started changing parts and getting things together to build up a new set of wheels. I'm pretty sure my bike weighs around 25, it may be 27. It really doesn't matter because it feels great. Just keep it how it is. Save your money, you'll need to spend it eventually as you progress, so why rush it?
Refs: Tito24, RiverSideRider, Stussy, Nettyspaghetti, Daniel24, Freddydapice, BrokenBMX, SuperstarDK, HardBMX_Tim. There's more, but I'm too lazy to look them up, haha.