I went from a juggle between 1st/2nd place to the very bottom of the second page. I thought I was doing quite well until today!

Any particular reasons why this could happen? I haven't really done any major changes apart from building backlinks..

give us more info to work with. There are so many possible reasons.

One thing you should consider: did your website sink down or did your competitor went up?

Which one of your multiple sig link is your website?

Aberystwyth Web Design

Competitors went up? No, definitely not.

did you change your sitemap or add pages?
I've seen that happen sometimes and it was linked with the sitemap.

Why don't you have any meta description?

Also, think about a 301 redirect from the non www. to the www. version of your website.

Did you continue link building. And yeah, changing your title may also affect in your ranking.

I think 301 redirection will penalized by Google and Yahoo correct me if I'm wrong.

You are wrong.

AGAIN

This is quite alarming. I've gone down to 5th page today. This has all happened in 2-3 days.

sorry to hear that. You said you haven't done major changing but you've obviously done something that pissed G off. Maybe cancel all the changes you've made in the last week or so and see what happens.

Also follow some advices posted above, your website is not super optimized yet.

the safest way is not to do ANYTHING. It's not a rare occurrence by a long stretch and very very often rectifies itself over 3 or 4 weeks.

Has traffic dropped off, or conversions reduced?

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