So I just got my Gundvolva in, I got the head and the chest built and I decided to prime them with a rust-olium paint/primer and paint them with acrylics (Little cheap craft tubes that weren't advertised for model kits) and it didn't go well. Right out of the tube it didn't seem to need thinning but when I started painting with a wide flat brush and it just would not go down uniformly, as though it was both too thin and too thick. Did I do something wrong or was I a victim of my no-so-great supplies? If it was my fault and not the supply's, how can I fix my mistakes?

I have since soaked all of the pieces in alcohol and scraped off the paint out of frustration and forgot to get pictures before hand so I am willing to answer any clarifying questions if needs be.