No, no need to separate if you have got two hideys (if necessary, make the little one a cardboard hidey that your bigger girl can't get into). Your two girls HAVE bonded; there won;t be any blood shed as long as you give the little one a chance to get out of a corner. It is all going pretty normally for guinea pig bonding. They know what they are doing. Please read the links and you will find that all dominance behaviours you have reported are well in the tolerable mild to medium range. Any loud screaming from the little one is submission, NOT hurt.