yeh if your sisters had that experience she can advise you but remember no matter how many peoples advice you get, it's your own decision at the end of the day and you've got to do whats right for you not what you've found was right for other people, and well it sounds like you'd like to look after them but you don't think your background is capable of bringing them up, so i'd be a bit wary of giving them up as in a few years everything will change and you'll be thinking right i want my kids , i can look after them now and you got to remember that you can't do that, once you give them up you can't get them back until 18, also thinks whats best for the children, if you physically cannot look after them then adoption is a good idea. Talk things through with your mum , ask her what she's feeling and stuff then you can also tell her everything. It's easy to say oh we can give them up for adoption and the issue will be solved, but when they're born you might feel differently.
by the way is this guy your boyfriend or you ex boyfriend becaus eyou've called him both so i'm confused?