If Phasta is pregnant like the preview suggests I feel like it would only make his mental state worse.
So far he's only minimally come to terms with how his body is changing and now suddenly he's growing a whole new human?! Not to mention the fact that in the preview Nakhun looked like the cat who got the cream in Phastas nest which - while being really cute - implies he's very happy with this turn of events. I can totally see Phasta now questioning if Nakhuns affection for him is because of the baby rather than because of Phasta. In a similar way to how he already feels unsteady because of how Nakhun treats the fact their soulmates as the only answer to anything.
Hopefully it would be the catalyst to Nakhun getting a few more brain cells of emotional intelligence and actually telling Phasta he cares about him for him.
Now that I'm thinking about it Phasta being pregnant would be another thing happening to his body unasked for that dramaticly changes his life in the span of maybe a month....not good.
We as the viewer have yet to see Phasta get any kind of sex-Ed about his new bodily functions (one of the reasons he's so confused) so even though he's been told in passing he can get pregnant, to me it feels weirdly similar to how Sheng Shaoyou was only given hints he could get pregnant and the truth only AFTER he was already pregnant. Pregnancy and parenthood are major things that effect the entirety of a person's life yet both Phasta and Shaoyou get thrown into it without even the knowledge its a possibility. From Phasta's personality I get the impression if he truly understood he could get pregnant he would demand condoms for sex or no sex at all.
....I feel chaos a brewing....