Why does it keep saying I tweeter stuff when I don't have a twitter account?

[sick of it]

ever since I opened a yahoo email account- it started doing this on my updates... i don't even have a twitter account and I closed my facebook account and STILL it will say I twittered ( I copy and pasted the following example):
"(my name) tweeted- This made u
s chuckle, too RT @dannysullivan: The Things Facebook Causes, According To Google, Yahoo & Bing, http://selnd.com/bAgYGX"

WHAT IS UP WITH UPDATES LIKE THAT? I never tweeted any of this- there is tons of stuff like this from twitter on my profile updates- How did it happen and how can I make it stop?
this is on my profile page in the "updates"- I can't open anything- it's just a list of things that my contacts say. EXCEPT that I don't have a twitter account- or a facebook account... Why am I getting updates from my self- on an account that I don't have- saying things that I don't say?