Citrus doesn't grow true to seed. Here in Florida, fruiting citrus cultivars are grafted onto sour orange stock, which is much hardier than table or juice cutivars. The grafted tree will make acceptable fruit for years, but eventually, the sour orange stock will assert itself over the rest of the tree, and the fruit will become sour, and the tree may even begin to grow spikes. Shock to the tree, or frost, can also cause the root stock to become dominant.
When they're small, it's best to knock off the fruit, so that the tree can allocate more resources toward growth, but I've harvested fruit from 1" caliper citrus trees.
Readboth, your citrus ought to have already put on blooms for the last 2 or 3 seasons, but since it was grown from seed, it's a wild card. It might be a dud and never produce anything for you but foliage.
If you want fruit from your citrus, your best bet is to purchase a grafted plant from a quality nursery.
Key limes are a great citrus to grow in a pot, if you don't mind the spikes. They also have the advantage of being everbearing, so once they get to be 3 or 4 years old, there will almost always be at least a few fruit on the tree. Enough to spritz onto seafood, or to make a homegrown margarita once in awhile ;-)
