I would think it's probably not baby. At 8 weeks, our babies can only really arch their backs. Their limbs twitch because of the muscle fibres, but they don't move as such. I don't think they're doing a lot of moving around the womb at that stage - it doesn't really start till 10 weeks.
Also, I thought you felt movement through nerve cells in your skin? So when the baby was strong enough and pushed harder on the side of the uterus it touched against the inner layer of your skin, which makes you feel it. https://www.birth.com.au/middle-pre...rnity/baby-kicking-and-hiccoughs#.Utw4MFE4ky4
Having said all that, I know what you mean about feeling what feel like baby flutters. I know they're not, they're the same gas bubbles phantom kicks that I've had since my son was born. They feel just like early baby movements, but I know what I'm feeling isn't, it's just too early. I know I'll feel them earlier this time, because my son decimated my muscle tone, so there's less of a barrier between the uterus and my skin, but I'm not expecting to till after 15 weeks or so. I do really like the feeling though, it reminds me of what is to come!!
x