Well the odds will vary depending if the overcards are suited, connected, what size of pair you have etc. But generally speaking you could say you are favored 55/45 holding a high pair to 2 overs preflop.

If you feel they aren't holding up, keep actual track. Sometimes in our minds we kind of overlook some of the ones we win when we expect to but remember every loss lol. If you keep an actual count and it's continually against you, I'd be changing sites. If for no other reason than for peace of mind.

All poker rooms use a RNG (random number generator) and I have found with a few sites that theirs suck. It's mathamatically impossible to create one that's 100% random but like with everything else there are good ones and others you have to wonder about. I've never played on that site so can't comment on theirs.