what's passion

Last night, i realized something new. I realized that I spend more time voluntarily on reading about and playing with photography, interior design, layout, filming--than doing things pertaining to medicine or science. It scared me. As of now my life seems to be definitely on the pre-med track, but that's not my passion. Or is any of the things listed above? I don't know which ones are hobbies and which ones are passion anymore. But I know I have no passion for science. I don't learn about nature for fun, but I do layout for fun. I don't just start experimenting with everything I have, but I do try eve rything I can to do some interior design, for example, by playing Sims :)

Anyways, the thought that I might be going into something that's not for me is scary. Really scary. I don't want to wait till my forties to realize that what I'm doing is not making me happy at all. I don't.

But another thing is, I remembered I wanted to study infectious diseases. I want to outsmart the bacteria and the virus. This is probably the only aspect of medicine that excites me. But in order to outsmart virus I need to do lab research, which I hate...

Life is a series of decision-making, and I'm stuck.