it's good before you buy something for trading or for investment so it's better to do a good analysis first. because a good analysis will avoid you from the risk you mentioned above, if my suggestion for now wait until the btc price rises first, because usually from what I observe ethereum prices will usually go up following the price of btc. it's just my simple analysis, you can apply your own analysis using a chart that is available on many websites, because if you only speculate it doesn't make any difference with gambling