Has adolescence arrived?

We have an adopted dog that is more or less 5-6 months old (it is not known exactly, but almost all of his baby teeth have already fallen out). Lately there have started to be changes in his behavior, she has become much more vocal and has started barking at friends who come over or people he sees coming through the door at night (he didn't do any of this before). We live on the ground floor of a building, so we heard a lot of noises but until now she didn't react to them. She challenges us much more, and unless she is very hungry or there are treats in sight, she has a hard time obeying. Yesterday she started kicking the trough with the food, and until she threw it all on the ground and made me see it 😂, he didn't eat it. SHe also gets up in the middle of the night to play, which he never did. She has also become more demanding of attention and can no longer stand alone for as long while we work in another room.

We are first-time parents, we have lived a lot with adult dogs but we had never raised a puppy. Is what I see the beginning of adolescence? Can be heat? I just want to know if this change in behavior is more or less normal and I should just be patient, or if I should be worried. She eats and goes to the bathroom normally, has energy, doesn't seem to feel sick. Thank you very much in advance.