Best advice, go slower on that trail.
If you are flying off the trail for correction errors, it usually means that the rider is going a bit faster than they should be. SKetchy is cool, but wiping enough that it's a concern is a sign of something else.
Now, if it's the bike actually feeling loose (verify this on pavement if you can), then that's a cause for concern. A wheel that's flexing through turns will feel about like the shifting of an underinflated tire. Wobbly could be a serious wheel true issue, a loose skewer (check them, always), or something else.
If you think the fork is misaligned, then do this:
draw a chalk line from a wall about 4 feet out.
set the bike on top of it so the tires are split in half by that line (front and back tires)
now put two plumb bobs on your handlebars, one each end...see where they drop. if one is in front of the other (use the chalk line on the floor for determining this), then your bars and fork are not aligned to each other.