Placing seeds in water and drowning them is a really bad idea that should stop ASAP. It may help with seeds that are 10+ years old but has no place in trying to germinate fresh seeds. Most likely your seeds have in fact drowned and are now rotting, unfortunately. You should use one method only and either wait until the root emerges in the water and then plant it or preferably, start by planting them in the jiffy pellet only. Seeds actually need oxygen to germinate and if you have soaked them in water then planted them in jiffies and then watered them again, this will lead to drowning, due to excessive moisture preventing oxygen exchange. After 12 days there is no hope of seedlings emerging, the longest I have ever experienced in over 35 years has been 8 days and that was with some rather old seeds. Normally germination takes place from between 2 and 6 days, all things being well. Cold temperatures being the only real enemy of normal germination. Sadly you will need to either replant (straight into jiffies is the best option) or buy some more seeds if you have already planted all the ones you had. Another good method to sprout seeds that is almost fool proof is to use small rockwool cubes, again sowing directly and not over watering them. If the cubes feel moist when you touch them with the back of your finger, this is plenty moist enough. Plant your seeds twice as deep as the seed is large. If your seed is 4 millimetres/eighth of an inch, plant it 8 millimetres/quarter inch deep.
Hope this helps,..... Organoman.