From the photo you sent my guess is you have a native plant sometimes sold as a wild flower or groundcover called Sundrops or Oenothera fruticose. It thrives in poor, dry soils so gardeners plant if by seed in areas where not much else will grow. It does self seed so if you want more of it just let the faded blooms stay on the plant and it will form seeds that will drop onto the ground and bloom next summer. It is your choice to call it a weed, a wildflower, a blessing or a curse. Keep growing, Marianne Binetti