Yes it can. It all depends on your body. No real way to tell how long it would take.
No. Go talk to your doctor if you want the piercing to close up that badly. Over time the piercing will shrink and will become unnoticeable
After 3 years chances are good it wont close, the piercing will shrink but not close completely.
It depends on where it is pierced. The lobes can take about 3 months to completely close up, where your cartilage can take 6 months to even a year to completely close up. It also depends on how long you have had the piercing. A piercing that you've had for years can take years to close (in my personal experience).
It varies, if you have had the piercing for a long time the hole might never close. It does vary, i got my ears pierced over 3 years ago and still close overnight.
If you've had the piercing for only four weeks then yes, it will close relatively quickly. My lip piercing was two years old and closed up in only a few days, leaving a small scar. If you don't want it to close but do want it to go unnoticed look into piercing retainers.
Well if you have had the piercing that long it won't close, however it will shrink over time. The mark left by the initial piercing will remain in place and will look less noticable over time.
A tongue piercing can start to close within a few hours if left without jewelry. However, it may take several weeks for it to fully close, especially for a piercing that has been in place for six years. Individual healing processes may vary.
There isn't a way to tell :/
Plastic surgery
It doesn't matter the location and age of the piercing...some of them will close in a matter of minutes and some will never fully close.
stitches...
It really depends on the size of the piercing and how new it is, the larger and older the piercing happens to be the longer it will take to shrink down then slowly close and heal up. You could be looking at anywhere from 3 months to a couple of years.