Braxton hicks or round ligament?

Ann

Im 14w 3 d and today since morning i have been feeling this really tightening feeling in my lower abdomen like my uterus or belly is contracting. Isnt it too early for braxton hicks.? It happened 2-3 times today , each time for about 10 seconds. Or is it just my ligaments stretching? This is my second pregnancy, i didnt feel braxton hicks at all during first pregnancy. This time im feeling every single pain more n more. Also was having some spotting few days ago, went to doc, she did scan and said i have partial placenta previa.