Thanks for the query.
Sometimes nuva ring can lead to side effects like nausea
If you didn't use it as per the schedule it may not give complete protection.
Though some of your symptoms are suggesting pregnancy
, just by symptoms we cannot confirm or exclude the pregnancy.
So you better consult gynecologist and go for pregnancy test. if the test comes negative you can take symptomatic treatment.
If the symptoms persist after this also you can choose some other method of contraception.
For more details you can ask me through: http://www.healthcaremagic.com/doctors/dr-sree-gouri-sr/63429