HELP GIRLS

Girls, I've got 2 babies and pregnant with my 3rd. With my last 2 pregnancies I walked everywhere but since becoming pregnant this time I've drove everywhere. Car tyres gone so yesterday walked my 2 to nursery, walked up to town round town and then home. Was walking for about 2 hours, got home sat down for 5 mins and then had to go and walk down to collect them.. Since yesterday I've had this pain on my right side, feels abit like a stitch.. But surly it can't be as it's still there? I'm 29weeks, has anyone had this? Should I tide it by or ring my midwife?