Interpretation Frustration: how far is too far?

I can already tell that this unit is going to be a challenge for me. Though I normally really enjoy both reading and writing poetry, Perrine's article has completely altered my view of it. I was under the original assumption that as long as my interpretation was not too far-fetched that it would suffice and ultimately be deemed "correct". Now though I find myself fretting over whether or not my analysis goes too in depth to the point that it doesn't fit all the criteria. Are there ever just poems that just describe an event outright or does every poem have a specific deeper meaning? And if both kinds of poems exist then how do you discern between which are just telling a story and which are trying to convey some significant life lesson? This unit's poems are a prime example of this confusion. To me a majority of these poems could just be describing an event or story; however, I could also find deeper meanings in them if I searched for them. I guess my biggest question is should I be searching and digging for them or should I sometimes just take them for what they're worth? The sooner I figure this out, I'm sure the process of analyzing the poems will be much easier.