Can't cross that line.

I have a few crushes... its funny... they keep happening... they are fun and then not so fun. I don't know what to do about a crush... how do I act? and once you admit you have this crush the feelings change... the flutters start and the awkward talk when you see each other. Am I stuttering? Am I sounding like an idiot?

By age 32 I think I have learned how to flirt... but I have to fight my impulse to withdraw... to get nervous and run away... literally. One crush is someone who I see at the dog park... we have tons in common- both designers and both have dogs! Ha... we work a block apart... but what else do we have in common really? I feel weird bringing up music and/or food- isn't that the kind of stuff you talk to someone about when you are "getting to know them talk" rather then someone I meet at the dog park talk... that talk is about our dogs... about politics... about anything but actual real life stuff.

The other one is someone I used to work with... not sure when it developed... it was a slow process... but all of a sudden it was there and now I cant help but IM when I see him online... which seems like more times then not. BUT what is IM really? Its not like I can see his expressions- or can assume one thing when in reality he meant another. What is a hint and what isn't? What is a sign on one side and what is really something totally different on the other?

I am not sure in both cases... what do I do from here. This is more then the hot guy who I see at the gym... these are two guys I talk to and have actual conversations with... could be considered friends with. Soooo... how do I make sure I don't get to know them so well that we fall into "hey, buddy" zone, but at the same time, how can I show I would like to get to know you better and see.... without looking like a desperate needy girl? There is the fine line... and once you cross it, you can not go back.