Hello missysweets, welcome to A2K.
I see lots of unanswered questions popping out to me from your post....
How long have you worked at this hospital? How long has the dr been your coworker? Are his attentions new? How happy are you in your marriage? Do you have small children? Does your crush on him stem from his attentions or did your crush start before he started flirting with you? Do the jokes from your coworkers bother you or do you think it's all in good fun?
There are so many possible angles to this that it really requires more background. Even then, we can only guess as to his true motives.