Ok, this is the deal: they say that we have several dreams per night but we only remember the last one(s), also, correct me if I'm wrong but isn't the brain supposed to be less active while we sleep? so shouldn't we dream less? the concept of time seems distorted when we sleep, for example, just today in the morning I woke up at 9:00 but I just needed to get up at 9:30 so I went to sleep again, then I dreamt a long dream that lasted for 3 days with a lot of details and other stuff that I think that it really isn't much important to talk about, anyway, I waked up after it and it was only 9:06, 3 days in 6 mins? that also reminds me of another dream that I had a long time ago, that lasted for a life time (with growing up, forming a family and other things until death), is it normal for dreams to last for so long?

The brain stays active as we sleep, it's just active in a different way.
Time has no meaning in dreams, it isn't applicable. Your perception during sleep tends to be very different from that in the waking world.

That's perfectly normal I'm afraid. By contrast, you can be asleep for 8 hours and only feel the dream for an instant.