Ok to take fluconazole (once), levothyroxine 50mcg and amitriptyline 10mg? any interactions with fluconazole and these meds?

Yes and NO: Both Amitriptyline and Fluconazole both are metabolized in the liver. So there is technically a reaction. However one dose of Fluconazole should not be a problem in any individual. Particularly on such a very low dose in a young healthy person.

Yes: Most antifungal on the azole(like fluconazole), inceases drug levels on your body by inhibiting its metabolism. Side effects may include toxicity and irregular heartbeat.

No problem: There should be no problem whatsoever with this medication combination. Best wishes.