Not heart beat hindi mo mararamdaman yun. 20 weeks may start ng parang bubbles na pumuputok sa loob na parang kabag, nag-iintensify each day tapos yung kicks talaga at 21 weeks. Iba-iba per pregnancy. Some would feel baby's movement earlier, some naman later pa especially if first time and kung chubby chubby and kung anterior ang placenta.