Have I been Google Slapped?

Hi

I've been trying to get ahead in Internet/Information Marketing for a few months now but new to Warrior so please excuse any newbie mistakes.

I've been trying to make some money from affiliate marketing via Clickbank using Adwords to drive traffic. So far so good, but my affiliate commissions were only just covering my Adwords costs - not going to give up the day job that way!

So I decided to go the natural route. I've tried to optimise my site, use relevant keywords, I even tried the Unique Article Wizard to submit a few hundred sites but still no major impact on my Google ranking.

I've recently started looking at backlinks and have been using backlink packets from a couple of guys off this forum. I added about 25 one day and a couple of days later I was able to find my site, ranking 480 on Google (woohoo!).

I added another 25 a few days later and kept checking on my site and it was creeping up, slowly but surely. Over the next couple of days it got to about 450.

I then made a couple of changes to my site based on some extra key word research I had done. The next day, I checked my site and it was nowhere to be found - certainly not in the top 1000.

Would making the changes to my site (only minor copy changes, nothing major) have had such an impact? I thought Google liked it when we updated our sites with new/better content?

Or, would the fact that I had added 50 backlinks in the last couple have days have raised Google's suspicions and I was being punished? I've heard about being Google-slapped and punished for backlink building, but surely one little referral site and 50 backlinks is small fry to Google and the kind of marketers they might go after?

My site is stopsweatingstartliving co uk and the keywords I'm going after are "excdessive sweating" and "hyperhidrosis" (not sure if I should share this info on here but hey, my site can't be doing any worse than it is and I doubt these keywords would be a big surprise if you've all been desperate to get into the sweating niche. Anyway, whilst it would be nice to make some money off this site, it's more a training ground to prove ideas and methods before I move on to other stuff.

If anyone has any help/thoughts/explanations, I'd be more than happy to hear them. Also, if there is any guidance you can give, even product recommendation, as to how to make SEO work, I'd be grateful. I don't mind putting in the effort, but so much with Google seems to be trial and error and it becomes difficult to tell what is actually working.

Cheers guys.