Preschool problems?

My son is 3 years old (4 yrs in April) and is in a mother's morning out program/preschool.  His teacher has expressed some concerns to me about some of his behaviors.

*HIs speech:  He does have some speech issues with pronouncing some of his letters and clarity of his words.  He was not a late talker just late in the pronunciation.  
*Social Anxiety:  My son has developed a fear of other children.  He is afraid to be near or approach the other children.  He will warm up to them after awhile but the minute they display any loud behavior he will retreat.  He also does not want to sit on the rug with the other kids during story/song time.
*Overstimulation:  The teacher states that he will become over excited and let out a yell or spin in circles.  
*Change in schedule:  My son also does not appear to like a change in the schedule of his class.  I do not see this quality much at home.  
*Tuning out:  The teacher states that sometimes she will have to ask him to do a task several times before he will do it.

My son's teacher has not come right out and said that he has a development disorder but has implied that she has some concerns about him.  She did state that he does know all of his letter, numbers, shapes, etc being taught in the class.  Should I have him evaluated?  

He is a very sweet, well-mannered child and hit all of his milestones on time.

[Kevin Kennedy, Ph.D.]

An evaluation with a developmental pediatrician would offer you useful information for sure. Based on your description I do not think such an evaluation is compelling, but it would be prudent nonetheless.