Your first concert was to see who and when?

The Beatles with The Righteous Brothers, Seattle Colosseum, August, 1964. 

Yes, April19,1973 in Atlanta.

I was class rep and arranged the group trip as a junior in HS. I got called on the carpet because a joint was passed down our aisle, upsetting someone's parents. Then I got props for not having let anyone take a toke, telling them just to pass it. I even got an apology from the parents, who had to admit that rubbing it out on the floor would have caused potential trouble. As much as we wanted to take a hit, I was relieved that everyone realized it was a school trip and abstained. As a result, we later were able to attend a Flames hockey game and the premiere of the Exorcist at a 2000 seat movie house.

The Blues Magoos (I'm Never Going Back to Georgia) in the Spring of '69 at the Ekman Civic Center in Old Greenwich, CT. I was 17 and a high school junior.

My first was a Battle of the Bands show at the then Charlotte Coloseum with The Grass Roots as main attraction.... don’t remember the others. I went with my ’girlfriend’, shapparoned. 

First real concert was The Doobie Brothers @ Cameron Indoor Stadium on their "Vices" tour.

aside from high school symphonic band concerts I played in [contrabass clarinet], the first "real" concert where I wasn't a player, was back in the summer of '83 at seattle's central tavern where blues harmonica player charlie musselwhite and his band were blowin' the walls down, almost literally. the speakers were refrigerator-sized, and the volume was so loud that my drink sloshed in its glass as I sat right up front and center. my hearing has never been quite the same since. shoulda wore industrial hearing protection. young and sorta dumb about it.