Hello Andrew,
Do you have some log from the build/deploy process? Which runtime are you using? How much memory did you configured?
Do you have configured some memory quota to you organization?
It's not a usual problem, since a common account on Bluemix has up to 512GB memory to define apps. But, if your account is a trial this limit is only 2GB and maybe you may have trouble with it.
You need to keep in you mind if you define a app on a dev space with 512MB memory, if you deploy it to a QA space it will consume more 512MB. If you deploy to production's env, your memory consumption will be 1,5GB on total.