Malware Twitter Link on Mac / Firefox - Avast stepped in..double checking- Help!

Hello!
Ok, so earlier I was on twitter and I posted a picture and later I noticed someone had commented on it and left a link… Stupidly (bit of a newbie to twitter and the excitement got to me!) I clicked the link and Avast went mad, with loads of warnings (3) (one big red box and two smaller ones) so I clicked x to get out of the tab the link had been set to open in, clicked on each of the red boxes in turn this got rid of them and then in a PANIC ran a complete computer scan (Nothing), checked that no apps had been downloaded to my twitter that would spam from my account (none), and changed my twitter password as a precaution… If those warnings from Avast came up does that mean nothing has happened. I blocked the person, reported them as a spammer and deleted the picture and reposted it afresh without the malicious reply and link…
I am a bit worried that it could have downloaded a man-in-the browser or some such that might not be caught by the system scanner - however I might be being slightly over paranoid. If those red boxes warning of an infection came up that means that avast stepped in and there is nothing to worry about and I can continue to browse and bank in safety?
Please help!

If those warnings from Avast came up does that mean nothing has happened.
impossible to say from your info, and you dont tell us what the avast popups did say. 8)

screenshots would have helped

Hi, Thanks for your reply…
I know screen shots would have been great but I completely panicked and needed to delete everything.
There was a note of the links (3… I guess to correspond with the three red boxes from earlier when I clicked on the link like a fool) in the ‘history’ part of the web shield and not the infections… (I have deleted that too now…so I can’t repeat the action to get you the screen shots! :o)
There was nothing in the ‘infections’ log and a complete system scan revealed nothing and having deleted the twitter post to get rid of the link so no-one I knew would make the same mistake I did out of curiousity, there is no record of it having happened.
I got such a fright when the popups popped up! One was very long and two were smaller… I actually can’t remember a single thing they said - post traumatic stress maybe?! :? I needed to minimize them quick (the avast popups) so I could get to my dock on the right hand side of my computer to get in to avast.
So there is really no way of knowing until something happens because I can’t remember and I didn’t take screen shots… eekk! (hmmmm…)

I’m just looking a google images of he avast popups and I’m wondering whether one of them at least didn’t say ‘infection detected’…
However as I said nothing came up in the scan but the three urls were in the history of the web shield.

Confused and very worried.
The more I read online… (a bit like googling illness) the more I become worried…
There has, however, been no strange activity from either my computer or my twitter account since the clicking incident this afternoon.