Yes!
My child is an only and has always been more comfortable around adults. In fact, I think she first crashed when she turned 4, and after getting extreme positive approval from adults for so many years she found out that once other kids became more aware of each other, they weren't so generous.
Personality-wise, mine is a people pleaser and loves everyone. Struggling socially was a huge problem, and I would have been delighted if a teacher recognized it. Her teachers thought she enjoyed being alone. She didn't.
School problems at 4 led to us contacting a neuropychologist who suggested social skills classes with docile kids only. We felt like they were too expensive and that she did really well around other kids who needed help. It was the non-social skills class kids that she needed help with.
What we did was really hone into any connection that she did make and do playdates and keep those connections and friends. It was work. But it helped her through. She's now been to three different schools and we skill keep in touch with all those friends, even when it isn't easy.
Other than that, it has been a waiting game. She's now seven and is finally starting to do okay. Part of that is having a great teacher who really accepts her. The other part is having been in enough classes to meet the people like her. Now she's meeting them. She's still a wonky kid, but it isn't so problematic.
If it isn't a problem for your child, it isn't a problem, but three years of waiting it out in my house were very difficult. She still fears rejection and just isn't willing to be as open as she was before, but she's getting a lot better.
Edited: In what I see, self confidence begins when a child feels accepted. If no one accepts you, it's really hard to feel good about yourself. Does he feel accepted? If not, maybe the teacher can help with that.
