I'm pretty sure that I just inhaled a staple (one that had been folded over & has no pointy edges.) would this cause any health complications?

Usually not. More than likely this staple will pass through your intestines without incident. However if you have abdominal pain or even lung discomfort i would f/up with a doctor to get an x-ray if necessary. Again i wouldn't be too worried though.
Get a chest X-ray. If you inhaled it, it can (and should) be retrieved from your lungs. If left in, it can lead to chronic infection. Its not an emergency, as long as you don't have severe symptoms (cough, fever). If you didn't inhale, but rather swallowed it, it will pass, but an x-ray will confirm the location (lungs versus GI tract). This brings a whole new meaning to "fine needle aspiration" (<-- doctor humor).