It's all normal for your son. This is who he is.
When you meet another little one, watch to see what is normal for them. Every kid is different, and few will be like your son in the ways you described.
I perceive letters and numbers the same backwards and upside down. I can tell they aren't forwards, but it takes very little more effort for me to read mirror writing or a page someone across the table from me is looking at. Some people are just wired that way. It hasn't caused me any problems, that I know of.
