Your first concert was to see who and when?

Foreigner, 12/3/78, Boston Gahden

1812 Overture & a Tchaikovsky Symphony at the Royal Albert Hall. I do not remember which orchestra was playing.  It was 1958 or '59. The cannon's echo may still be running round in the Gods!

I was in the local C of E youth club for about 5 years and a few times a year we would go to London, usually the Albert Hall or RFH.  In addition to "classical" concerts (baroque through romantic & 20th century periods) I remember Acker Bilk's Paramount Jazz Band and Monty Sunshine's "Trad Jazz".  We also went to the MJQ at the RFH in (I think) 1961.

Bo Diddley. October 16, 1960. 
State of Texas Prison Rodeo, Huntsville, Texas, north of Houston. I was 14, went with my 18 year old sister and her husband.
Outdoor arena. A stage was set up for Bo and his incredible band in the arena.
The Prison Rodeo was an annual event with prisoners as the participants, Even though many of the participants were Black, the bleachers were still segregated at that time. Those stands were rocking while most of the Whites stayed relatively still.
 

Simon and Garfunkel, Sept 1966, Heinz Hall Pittsburgh.  Homecoming concert University of Pittsburgh

Simon and Garfunkel, Sept 1966, Heinz Hall Pittsburgh.  Homecoming concert University of Pittsburgh