Hi mama! Normal lang yan usually sa 35 weeks, especially ang back pain dahil ang bigat ng baby and hormones are loosening your ligaments na, pero mas okay pa rin to check with your OB para sigurado na hindi something else, lalo na kung sharp or persistent yung pain or may spotting pa. A few of us first-time moms dito sa group namin nag-complain din ng same thing around that time, so you're not alone!