Firefox session lost

Please bear with me, I am NOT computer literate.

I use Ebay and Facebook a lot and end up with many, many files clogging up my registry and use ccleaner to clean 'em out. I shut my laptop down last night with c. 80 tabs open and when I booted up the computer today Firefox started opening automatically. With only the 1st tab showing (before all the rest populated) I shut it down and then ran ccleaner.

Now all my tabs are lost!! I seem to recall having this problem a few years ago and went somewhere to retrieve them, but darned if I can remember or find what it was.

Can anybody tell me simply if there is a way to restore yesterday's Firefox session please or has ccleaner wiped it permanently?????

I have tried Googling this problem with Mozilla as the main search term but cannot find an answer there which is why I have come here.