Aw, yan ang pregnancy naman talaga, ang body mo is doing so much work na parang may weird sensations ka from time to time! A few of us moms felt the same thing during pregnancy, parang cold sensation or heaviness sa tummy, at nakita namin na normal lang siya lalo na around that stage when baby's growing fast. But since you're 4 months along, better check with your OB just to make sure everything's okay lang, kasi sometimes it could be nothing pero peace of mind is priceless, di ba? Congrats sa pregnancy, mama!