Pain in the Butt!

Pauly
Excuse the pun but I'm looking for some advice regarding a pulled glute muscle on my left side. I'm 12 weeks pregnant tomorrow and for the past few days Iv a dull pain in my left glute area. I know it's muscle as Iv had muscle injuries in the past and am familiar with the pain. Iv no idea how it happened and it's getting worse each day! 
Any idea how I can help cure it? Any specific stretches I should do to ease the pain? Thank you!