Nyssa should've known the man on Logopolis wasn't her father. Her father was an old man, and the imposter, the Master, had somehow rejuvenated her father's body. The Master tried to make her strangle Adric and the Monitor of Logopolis with the help of a bracelet. The Doctor, in his previous body, pointed out the Master to Nyssa; the Master made her lash out at the Doctor. Nyssa wasn't the type of person to display anger or sadness in front of others. She'd replay the events of Logopolis in her dreams. She wanted to lash out at the Master as well as the Watcher for bringing her to Logopolis, but she couldn't.
After one of her nightmares, she woke to find the Doctor sitting on her bed in the TARDIS.
"I heard you screaming," the Doctor said. "Were you having a nightmare?"
"What was it about? The Urbankans? Cranleigh Hall? Adric?"
The Doctor scratched his head. "Oh, yes, Logopolis. I can see why you'd be affected by that."
"Sometimes I wish I could hurt the Master or the Watcher."
"The Watcher? Why the Watcher?"
"He brought me to Logopolis. If I never went to Logopolis, I would've never met the Master."
"But if the Watcher didn't bring you to Logopolis, you would've been on your own somewhere in the universe. And you wouldn't have met me."
The Doctor kissed Nyssa. The kiss progressed into kisses under Nyssa's neck. Moments later the two were naked in her bed. From there, the Doctor was inside her. The Doctor flipped Nyssa on top him. He let her ride him. She kissed and rode him aggressively, letting the frustration of her experiences with the Watcher and Logopolis out of her system until she came. After the Doctor and Nyssa were done, they spooned together.
"You know, Doctor, I think I'm starting to like the Watcher…" Nyssa said as she dozed off to sleep.
This time Nyssa dreamed of the Watcher bringing her to the Doctor, in his current body. From there the two walked inside the TARDIS, heading off to somewhere in time and space.