Found: Doctor time travels, scotland, medicinal night flower, historical romance

All I can find is outlander when searching details. The books is about a female doctor who goes to a castle in Scotland searching for information on a medicinal flower, that no longer exists. There is a painting in the castle with the flowers in it and she ends up traveling back into past scotland, where she meets the old owner of the castle who ends up being her love interest. I know they find the medicinal flower at some point and realize it only blooms at night or under the full moon, something like that. Also there is a scene where she does a medical procedure on a guys skull to relieve pressure while in the past. Definitely an adult book as I remember mature content.

Night Lace by Emma Merritt?

Seeking a cure for a mysterious new virus, devoted doctor Beth Balfour travels to a far-off Scottish castle to find a remedy described in an ancient text: a delicate, silvery flower called Nightlace. It exists, to her dismay, only in the portrait of a seductive eleventh-century laird.

You are a Saint, thank you so much! I couldn't find the name anywhere.