I don't think there are two Vikrams. I think he was pretending to be good all along. If you remember when Shankar went to find out more about Vikram he found out that Vikram was there when that incident happened with Rashi. And as he said to Rashi that you too loved me.... I think previously when he was asking Rashi why she is angry with him, he must not be sure how much she remember....
Btw I think Rohit is looks better in negative character but I am feeling bad for Vrinda, really like her.