So my plant is about 23 days old from seed. I just notice another sprout. At first I thought it was a leaf that had fallen off but when I grabbed it, it wouldn't come out easily and I didn't wanna pull it out. What is it??
This kind of thing actually happened to me this year, except the little baby plant was growing out of the same spot my plant was. I don't know how it happened at all, I wish I took pictures of the incident but I transplanted it, grew it out, and it was a female and is currently budding, I'm glad I didn't just rip it. In your case it probably isn't weed because it's growing in an entirely different part of the pot.
Sounds like an overwatering problem. Let that soil dry out some before watering. That plant should be way bigger. She hasn't had to build roots to find water. No roots no fruits