Random ARAM

I'm just venting here but I play ARAM daily, usually 5-10 times, and for some fucking reason I believe that it is not random at all... Some days (like today) I get the same champion multiple times in a row... Also, check this out, I once had 2 rerolls, reroll once didnt like the pick then wasted a second reroll and got my first champ. What the actual fuck is going on here. Is aram even random or do they just pick a certain line up at random daily. I'd really like to know what is actually going on here... Kinda getting sick of seeing the same champ, being played myself or by someone else, all the time only on certain days. I know I cannot be the only one who has noticed this or have been the first to bitch about it but its fucking annoying.