how deep did you plant 'em? The seeds only need to be about 1cm deep. Some people leave them overnight in water first to soften up the shells. If you planted deeper, try carefully scraping some soil back. I personally germinate them with the wet towel method and then pop them in dirt when I see the root first pops out - usually takes 1-3 days.

What are the temps? Ideally for germinating you want between 24-28 C.

What's the soil like? You need to have a nice light airy mix. adding peralite can help. never pack soil down, keep it nice and loose. If it's too packed there won't bee any air for the root when it emerges and it will die.

How wet is the soil? You really only need it to be moderatley damp, not wet. if it's too wet, again there won't be any air for the root and it will rot as soon as it emerges. you can spray the soil with a mister or keep it covered with clear plastic, but once they pop up remove it and let the top soil dry a little before watering - the root will be 2-3 inches long by the time they sprout so it won't die of thirst.

I'd say that 2 weeks is more than long enough. would suggest you dig one up and take a look. it may well have sprouted then died.