Couple questions. Eastern Newt and Fire belly newt love?

What's good? I just got myself a couple weeks ago 3 fire red belly newts for my tank with 2 eastern newts and many other aquatic creatures. Anyway, I asked the lady at the store if I can place them all together and she said it's fine. These two newts, one being a FBN and another being an EN, they're inseperable. They are always together, and when I try to move them, they go right back to eachother and just sit there.. ALL DAY. Is it possible that they're in love and might possibly mate? I don't even know if these two can actually breed, their both different.

Another thing is, since they haven't moved from the spot. The green eastern newt's face is kind of darker now. Like a black-ish color to his face. Is that normal? I never seen that before and I had these eastern newts for about 5 months now. They're so cute together though. Lol.

Well, i know this is not what you want to hear, but that mix is an awful, awful idea.
For starters, they are all wild-caught from very distant places, which means there is a risk of exchanging patogens.
Also, Notophthalmus viridescens males court by amplexus, and they are not very good at determining their own species so they´ll amplex a C.orientalis too, which can mean the death of it by drowning.

There might also be agression to each other specially during feeding.
You also need to consider that both are toxic, but N.viridescens produces a substantially larger amount of toxin.

I ignore what other things you have in with them, but i seriously recommend that you read this:
Caudata Culture Articles - Species Mixing Disasters

Please, separate each species in their own tanks.

Incidentally, no, they wouldn´t be able to hybridate. And they are not social creatures so they don´t "feel" anything for each other, either. It´s purely coincidental given the fact that they are stuck in a tank, it doesn´t reflect feelings.

Thank you! Since you told me that I went out and bought a big temporary tank for the fire belly newts. I'm scared for the eastern newt, I feel like it's to late for him now. His face is black, but he did eat today after I took out the other newts. Happy about that, I hope he can be healthy again. Thank you though for your help!