Ranked Broken?

I Have started this game maybe ten days to fourteen days ago. I started playing ranked after I reached 30 since I was doing very well in my normal matches. Once I finished my eight placement matches I was placed Iron four. I found it odd considering I was usually the only one doing well when I am only ten to fourteen days in. After I was placed I'd be matched up with golds four to one. I found this very frustrating since I kept getting destroyed as a team left and right. I somehow would manage to do well most of my matches no matter where I played but I would always get teams full of toxicity and teams that lack knowledge to do well. Is it just me or does it seem almost impossible to rank up? I play Bottom lane now either role and it always seems top, middle, and jungle does awful. I will then try top or jungle to try to increase my odds in ranked but it still ends up the same. I tell myself maybe I am just not good enough, but I do everything I can but many people seem to make it impossible to win. Any advice?