Aw mama, constipation during pregnancy is super common, a few of us went through it din around that stage kasi ng hormones at ang baby bump natin! Try drinking lots of water, eating more fiber like fruits and vegetables, at light walks if you can, honestly those helped my mum friends a lot more than expected. But since this is your first time and you want to be extra careful, best check with your OB din to make sure everything's okay at they can recommend something safe for you and baby. Rooting for you!