I think I probably had physicals with our family doctor before I can remember now, but the earliest ones I do remember were school physicals from when I was 6-8 probably.
They had a mobile medical unit, either an RV or a trailer, which was brought to the parking lot outside the school, and it was there for several days as they gave physicals to students in different grades.
They would have small groups of us, three or four, and both boys and girls, (I think it was done alphabetically,) be led from our classroom to the medical unit. Inside it was divided into two sections, the waiting room and the exam room, with a fairly thin wall of cheap fake wood paneling between. We always had to wait at least several minutes in the waiting room while they finished with the exam before. I always liked the toys they had in the waiting room, but it was only the first year where I played with the toys innocently. That time I didn't really know what was about to happen, the other times I was preoccupied with nervous thoughts about what would happen once I went into the exam room, and also thinking about what was being done to my classmates who were in there just before me.
The first year, the nurse or assistant came and called my name, then led me into the exam room where the doctor, always a female, was standing in front of the exam table. She greeted me, talked to me a little about how I was feeling, then said we would get started. That first year, I was told to get undressed, it was always in front of them, everything off except my briefs. The next year it was everything off, including my briefs, but I could leave my socks on. The year after that it was everything off completely. Each time I would get a nervous thought about my classmates being just on the other side of that thin dividing wall. That year when I was just wearing socks left the greatest impression on me, I felt more exposed and naked than I even did the next year when I was totally naked. A few times as an adult I've been undressed to nothing but socks, and it always takes me back to that memory.
They had me step on the scale, measured height, had me walk around so they could check my gait, I think bend over trying to touch toes, and that sort of stuff. Then, I was asked to use the couple of steps up to the exam table and sit down. The doctor listened to my heart, and breathing, checked my throat, ears, and reflexes, and took my temperature orally. The doctor then asked me to lay down on the table, and she felt around my arms, legs, abdomen. She then lifted the waist band to my briefs and pulled them down in front, and felt around my penis and under my scrotum. I must have squirmed around because she asked if that tickled, and I nodded, a bit embarrassed. I probably blushed all over.
The two other years I remember getting off the exam table and standing on the floor while the doctor checked around my penis and scrotum. I didn't have my briefs on, so nothing to pull down, either of those times.
That's about as much in detail as I recall. I would get dressed, and go back out to the waiting room. The first year, maybe two, I waited for whoever in my group hadn't had their physical yet, and I played with the toys. There was a sense of nervousness now, though, as I thought about my classmates being examined, and marveling at what had just happened to me. The last year, I didn't have to wait for the others, I just was sent back to class, with my head spinning over everything.
After that first time, whenever I'd see that mobile medical unit there outside the school, I'd get butterflies, and the anticipation would build. After my last year having a physical, I didn't see the medical unit again, so I guess I'm lucky my class was one of the last to have that experience at our school. I certainly think that was where my Medfet began, as far as I can remember.