Fish Behavior

[Betta Lover]

HELP HELP HELP ,

My fish started to battle each other last night for no reason . I'm so confused . I'm not really sure why this is happening, but I think it might have something to do with my new power blue dwarf gourami.
Just to let you know, my gourami has been building a rather large bubble nest, " which is normal ", and he has been attacking my dwarf puffer fish. I am very aware that dwarf puffer fish nip fins, but mine act like perfect little angles . The reason I'm confused, is that my dwarf gourami usually has a small bubble nest near the floating water plants, but I have never seen him act like this at all.I think he might be acting like this, because he might be in the mood for spawning, but I'm not sure ???

Thank You In Advanced
Betta Lover