Hello , hoping somebody can help me with this teaser.
I have basic gardening knowledge , but not to the extent where I could be 100% sure if something is a plant or a weed..

I planted some seeds into pots around late April time.. In one pot I put in cosmeas and pansies , and in another pot I put in chives and coriander.

Around late May/early June I transplanted the cosmeas and pansies into the garden..
The cosmeas having a distinct appearance of "two long leaves" similar to helicopter blades..

After a couple of weeks in the garden the pansies were growing well , but all the cosmeas had disappeared , not sure if something had eaten them or if they had died..

When I was watering the other pot with the coriander and chives I spotted another plant growing (with the distinct appearance of "two long leaves" similar to helicopter blades)..

I thought it must have been a seed from the cosmeas which had found it's way into the pot with the herbs , so I took the plant out , gave it a small pot of it's own and have kept it indoors on a window sill where it's growing steadily over the last three weeks..

The only problem is , Im pretty sure it's not a cosmea and now think it may be a weed which I have been watering every other day..

Does anybody know if this is a plant or weed ?
Here's an image of the item in question.
http://img157.imageshack.us/img157/6...orplantph9.jpg

The distinct features are the long leaves which have a dark spot along the centre line..
Where the stems branch out from the main stem ,it's as if they're attached by a clear sellotape..
A small acorn like thing has appeared near the top of this plant..

I really have no idea if this is a weed or plant.

Thanks for any help with this...