Shuffle Play not a true shuffle

[mgzwarrior]

Plan

Premium

Country

USA

Device

iPhone Xs Max

Operating System

iOS 13.0 (Beta)

My Question or Issue

I have a playlist on my account that I frequently add 10-15 songs to per day.  After adding a group of songs to this playlist, the next time I tap "Shuffle Play" the first 5 songs that are played are from this newly added list of songs.  This seems like a flaw in Spotify's shuffle algorithm.  Is this behavior expected?  Can anybody shed some light on this strange issue that I am having?

Thanks in advance.