Hi Padma and everybody else on this very interesting thread,
I have researched the whole laser hair removal thing for quite some time now, and I am myself on Session two on my face.
I have had the same exact problem that you and others are describing, in fact, I am going through a period of visible upper lip dark hairs right now, which is very annoying and embarrassing.
Here is what happens with hairs after laser sessions:
1. Hair that has just been "zapped" will come to the surface of your skin, because, after the follicle has been "killed" it, and the hair attached to it, will have no other place to go, but up. This process will happen between the time right after you get "lasered" and day 20-25 after the laser session. You will notice, right as you are getting treated with laser, that some hairs will seem to be "jumping" right out, and you will smell the singeing, and later on , during the day, these hairs will come out by just washing your face with soap and water. Most hairs will come to the surface and fall out between day 10 and day 20 after your last laser session. It is important to resist the temptation to pull the hairs out oneself, and let the hairs fall out on their own. It is important to let the follicle die on its own and not pluck out any hairs, aside from the ones that come out very easily, offering no resistance. If a hair offers any type of resistance, just leave it there, otherwise you will pluck it out, it won't be dead, and it will reappear stronger than ever weeks, if not months later. I was advised to just do washing and light scrubbing, but no plucking.
2. Hair that is dormant, i.e. not in the active growing phase (the anagen phase), will sometimes be stimulated by laser treatment causing the area to seem to grow hairs that were not there before, or to look thicker and/or coarser/darker. This is what is happening to me right now. It is good to let these hairs stay there, and not pluck them out, no matter how uncomfortable that might feel, and wait until the next laser hair session: it is important to ask the tech to up the settings a bit and go over these hairs twice, so that th hairs will die within 1 to 20-25 days.
The one question that I still pose myself is how long I should wait until the next session. I am scheduled to go for Session 3 about 5 weeks after session 2. It looks like there are going to be plenty of hairs to zap, but I wonder if waiting longer will provide even more hairs to zap.
How long do y'all wait from one session to the next?
My recap: Session one: a few hairs seemed to jump right out,. Then about 2 weeks later, lots of hairs were gone but some were still visible on my upper lip. The tech did a touch up on week 3 1/2 (I was there for another area). I then went in for Session two after 5 weeks from Session one. Some hairs jumped out right away. After two weeks I had no hair anywhere, including the upper lip: it had all fallen out. Then, now, after 3 1/2 weeks after the last laser session, I see hairs on my upper lip and it is a nasty feeling, because I had gotten used, even if for only a brief period of time, to being totally hairless.
I hope this helps,
Andrea