Joe Jonas celebrated his 29th birthday in New York City on Thursday (August 16), but his fiancée didn't seem to be in the mood for birthday cake and balloons.

In paparazzi photos obtained by TMZ, Sophie Turner appeared distressed as she sobbed into her hands, holding onto Jonas for support as they walked around Manhattan.

In photos taken later in the day, Turner appeared to have calmed down and looked to be in better spirits, but just why was she crying to begin with?

Well, turns out it's no mystery: On Twitter, Turner clarified the reason for her tears, writing, "Thank god I have a loving fiancé. Periods are a bitch."

See below:

Turner and Jonas were first linked together in late 2016. In October 2017, the pair announced their engagement.

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