Hash cookies are FAR more potent than smoking. Think about it like this (not perfect but it's the right concept): When you smoke it's like you have a cloud with THC particles inside your lungs. The longer you keep it in the more THC will touch your lung walls and the higher you will get.
When you eat hash or weed you have it in your stomach, nowhere to go. Every single particle of THC will be absorbed, and you will get FUCKED if you eat as much as you smoke. Read my thread "Cake OD" if you want an example of how overwhelmingly strong it can be. I would say the high from cake is anywhere between 3 and 6 times stronger than that of smoking (very rough estimate and some may disagree)
Have a cake but less is more for the first time, don't waste a half ounce of weed just to feel like death for a few hours