Is methadone causing her mood swings?

I have been dating a great looking girl for about 2 weeks.She has a fun,playful side ,but also a very moody ,bit=hy and bossy side.She must like me because she wants to be around me.But I have a hard time reading her because she shows almost 0 affection.She is on methadone,and what I want know is could methadone be producing these mood swings. I would like tsomeone to tell me what they personally know about it. Thanks

Comming Affects of Methadone Include:

Psychological: Drowsiness, sedation, dizziness, lightheadedness, mood swings (euphoria to dysphoria), depressed reflexes, altered sensory perception, stupor, and coma.

Physiological: Strong analgesia, headache, dry mouth, facial flushing, nausea, constipation, respiratory depression, muscle flaccidity, pupil constriction, and decreased heart rate.