Should I IM him cuz his SN is on his Facebook?

I want to IM him on AIM cuz he's never on Facebook but I added his SN last night and he's been on all the time cuz he's on his cell but i haven't IM'd it yet... when he's on Facebook we talk but like I wanna tlak more cuz he's super chill, should I IM him on AIM cuz he doesn't know I have his SN, but it's on his Facebook...