changing position

my position in google search is changing like crazy
in the past week going from nowhere to page one. i am in the process of link building so should i stop to see what is going on or should i continue

Could the link building be what's helping you or is the google bot just finally getting around to your site? Check your log files.

well it seems that google was in my site for a week
but it is gone now
i was indexed before and have been in the first page for a few phrases
all of a sudden it moved up with the phrases that were more competetive
which is fine but now my index page is not in in the first ranked page for one of my phrases while it is for other ones very strange maybe i linked too fast with this phrase

It still sounds like you're in good shape as far as the site goes. I guess I'd leave it alone now.

It's normal to occasionally have big changes. Eventually you will probably settle somewhere between your old position and new position.

How long has the site been live?

site is actually an old site but i just started seo for about 4 months now
i guess i should leave everything alone for a couple of weeks and see what happends
here was the crazy thing
for one of the key phrasses i am number 4 for my index page in 50% of the data centers but in the other 50 another page is number 35 and the index page is nowhere
but it seems to be ok now i am in the first page now i just have to wait and see if it holds

it seems that it is settled pretty high as of now
i guess my link building worked better than i expected