Well done for taking the plunge Dan and welcome to the club.
I don’t think it looks too dark, it matches your sides. However, this is after session 1 and you have two more to go so maybe just a shade darker on the next two sessions. Having said that, It does fade / settle after the first month or so I wouldn’t worry too much about the darkness now. In hindsight, I wish I had gone a tad darker but I bottled it. I’m now booked in for a 4th session touch upon in 3 weeks. What shade is that you’ve had done?