You have yourself in a jam.
The RIGHT way to do it would be like Troy-Curt said. Strip the car back down, re-seal it, then start again.
You have other options that aren't as "correct", but are doable, and CAN produce a stable, lasting job.
Seeing as you have ghosting, you have almost no choice than to respray the basecoat. The question is whether you are planning on taking all of your paint back off or not first. If you feel that your original sealing job was adequate, there is no reason you cannot scuff the clear that you have on there now, reshoot your basecoat then reclear as long as you keep your thickness to a minimum.
No matter if you strip the car and reseal or shoot over your existing paint, shoot your metallic in 3-stages. Put it on "DRY". That is, turn up your air pressure and extra 3-5lbs, and give yourself an extra 2-4" of distance from the panel, and increase your spray speed about 15% (that is, how fast your moving down the panel as you spray). Put on two coats like this. Just get good coverage without the paint being very wet. The paint on the car should completely flash within 2-3 min. With metallics, I like to see it flash in the 1.5-2min range. After the paint has flashed, put on a second coat just like the first....dry! Then, the third coat, give yourself another 5-10" of distance, turn DOWN your airpressure to about 3-5lbs below normal, open your fan up about 20% and put on a light/medium coat that is over-reduced by about 5%.
What's going on is you are putting down a base coat with the first two coats....just to get the color of the paint there. You don't really care what the metallic pattern looks like, just so long as the layer of paint is uniform and there are no areas that are "pooled" or that are wet longer than the rest of the peice. The last coat is just to put a random pattern of the metallic on the color that you sprayed the first two coats. The last coat should be sprayed to where there is allot of over-spray or "Fog". The extra reducer helps the heaviest particles in the paint (the metallic particles) to stick when they hit the panel. Standing back furthur and opening your fan up helps keep you from developing streaks and makes the metallic pattern more random. The idea is to get a good solid flat color, with a random metallic pattern on the top.
Anyways, good luck, and post some pics when you get them!
The 'hopper