By the way, it's more than likely mephedrone.
Maybe where your from they sell mephedrone for MDMA, but I've never once experienced that. All the 'molly' powder I've ever gotten has tested positive for MDMA. The world is a pretty fucking big place, and saying "it's more than likely mephedrone" to everyone on Earth who buys powdered MDMA is quite ridiculous. It really depends on where you live, and whether or not your finding the right dealers, which obviously you aren't.
My point is, OP, test your powder/pills/rocks rather than listening to someone on the internet telling you that your drugs are probably not what you bought, just because they can't find the right dealers/don't live somewhere with the right dealers.
Also, it's totally possible for people to put more than .1 in a pill. Some pills are really big, and .1 doesn't look like enough in them, so dealers may want to put .2 in and sell them for twice the price. Also, if your buying .3 anyways, and it all fits in 1 capsule, the dealer may want to put it all in one as to not waste more. I also know some respectable dealers who have retarted buyers who don't know what .1 of MDMA actually looks like, so they add some fillers, like caffeine, into pills. But they're still selling them for what .1 is worth.
There's also a possibility that your being ripped off. Can't tell you for sure.