3 hours sleep the past 37+ hours?

I had a trip with some family members to Norway with car.
Last time I had a full sleep, were Wednesday morning, I had slept from Tuesday about 11pm to about Wednesday 7am in the morning. An 8 hour sleep.
In the morning (wednesday) I had some Yoghurt and Juice, not that much but enough.

After that we went to the whale safari that were on a boat from like 11am to about 8pm. We were not very active in the boat, we sat down most of the times but also stood up, walked around etc. We were also quite tired as we had ate some pill in order not to get sea sick, and they said that the pills may make ones a little tired. I half slept for about 30 minutes in total.
On the boat around 5pm we had got some soup and a sandwich, not very much food though.

Then when it was over, at 8pm, we drove to a place, took us an hour maybe. We ate some food at a restaruant. It was quite much food, and it made me full.
Then from 10pm (at wednesday) to about 4am (at Thursday) I sat in the car while my dad and sister drove the car. I was maybe sleeping for a total of 1 hour, but I did it in small periods during the trip, except for the last 3 hours because then I were fully awake and didn't feel very tired.
Once at 4am (thursday) we arrived, and I slept for about 2 hours, then I woke up by alarm and ate a breakfast, sat down for about 1,5 hours until going off again but this time just a 2 hours ride with car.

Got on to the city, walked probably 3km and cycled 5km, I didn't feel tired at all. And yet I haven't.

Now time is 8pm (thursday), I been up for 37 hours and I count a total sleep of about 3-4 hours maybe. Which in my opinion sounds very little, but I somehow just ain't feeling tired.
And I just want to know if anybody knows the reason?

During the trip on the night at Thursday, about 2am or so, I were having a 200mg coffeine pill, but I don't think that one would make this much sense, because I use to take it quite often (using as pre-workout supplement), but really, is lower than 4 hours of sleep in the past 37 hours bad or something like that?

I don't feel tired at all right now, I had plans since this morning to go get my workout done in this evening/night and then sleep, but I am not sure if I may do so when I think about how not much sleep I have had.

But still I am quite interested in how come I'm not tired?

[edit]
Forgot to mention that I also been eating today (thursday) at daytime, and then dinner around 6pm, and I ate quite a lot. If now that info matter too or so.