Sounds like you have a hot spot, usually from the top wire to the positive post (the "metallic taste" is a giveaway). Just pull out your juice with a syringe, clean out the tank and rinse the wick/coil with water, and do some dry-burns until all the gunk is burned off the coils & wick - it won't harm either one. Then refill & after a few vapes, you should be good to go again. You only need to go through the break in process with the ceramics one time, after that, they are fine no matter how many time you clean them.
While your are doing the dry-burns, make sure the coils glows evenly. If the top (or bottom) wire glows first, you may need to tweak it a little (make sure it hasn't come away from the wick), but it usually settles in pretty quickly.
With the AGA-Ts, the positive post is pretty far from the wick, so it's a common problem. Next time you re-coil it, put a small Stainless steel washer under the top screw to take up the distance, or bring a little extra wire around the top nut & wrap it once around the top wire going back to the wick (essentially doubling the resistance on that leg)...that works every time.
Good luck..