No swelling. Maybe a tiny bit of bruising, visible only to you and easily covered by make up. Buy some arnica gel or cream if you are worried and dab a little on the injection sites afterwards. Be sure not to take aspirin or anti-inflammatory medicine before treatment or you may bleed. Some places also say no alcohol for a few days before hand.
Thanks all, you were right - no swelling. I went straight back to a meeting at work, no-one batted an eyelid. I'd had visions of me sitting with a hand clamped to my brow in a concentrate-y style, but no need.
I am now going to peer into the mirror. A lot.
How long did others take to see effects? I am going back in 2 weeks for possible top up, I hope I see difference before then.