HELP: Painful Latch

***Some back story: My son was latching on fine at birth, but then had trouble at a week, so I used a shield. At one point I had to use a pacifier with a hole in it because he wouldn't latch on. The shield came off at about 4 weeks. I use a bottle every once in a while when mommy wants more than 3 hours of sleep. ***Here's my question, what to do to help him open his mouth to latch onto my breast and not my nipple? He hurts me very bad, to the point that I bleed. He is so lazy to open his mouth and only sucks in (like a straw) when its feeding time. I've gone back to the shield to prevent anymore bleeding and sore nipples. I've bought Medela shields that help bring out the areola but it doesn't seem to help. ANY tips please? My son is now 7 weeks old.