Hi Pippi! Welcome to the board, I'm new myself and have found it to be a great support.
My word of advice is BABY steps. You don't have to tell him right away you want to have sex with him, or think about it. You can say things like you think about him a lot...or that you feel your caring is much more deep than casual.
He already knows.
I was a bit oblivious to this until recently. I thought my therapist had no idea, and I've only been with him a year.
I was there tonight as a matter of fact, and my sessions have ended but I figured out a way to go once a month.
He clearly stated he would miss me and he would 'try not to worry' about me.
I wanted to jump on him right there.
You can't do things like be friends with his dtr on facebook, but its OK to think about it.
I dunno, once I talked about it, the intensity went away a little.
Stay grounded. Breathe. Just say 'frig it' and get it out of your system. You will sleep better~!
goodluck!