Salam! Ooh interesting, I haven't personally seen this but a few of my mum friends mentioned weird skin changes during pregnancy, one had dark patches, another had redness on her palms. Yellowing at the corners of your palms could be salah satu of those pregnancy hormonal things, tapi since it's your first time pregnant and it just appeared tiba-tiba macam tu, best check with your doctor or midwife just to be safe, can? They can tell you if it's normal pregnancy stuff or something else. Don't worry lah, pregnancy does funny things to our skin and body!