This looks like a job for Dylan, he knows his drugs...
You didn't make that sound very good!

Anyway, if you're unsure about drugs you should always ask a Doctor, Pharmacist or Nurse. Not random people from the Interwebz!
Naproxen is a NSAID (just like Ibuprofen or Aspirin). All NSAIDs can have side effects to varying degrees (even those you buy over the counter) and Naproxen will be prescribed to a patient instead of Ibuprofen for various reasons (medical history, symptoms etc). Seriously, ask the person who prescribed them to you if you're worried mate!