Flashbacks

Okay, some background info before my issue: I was pressured into sex by my ex. A lot. Especially oral sex. I absolutely hated it. I told him I didn't want to. I eventually got out of the relationship, and I'm so proud of myself for that. But now, with my current boyfriend, I can't do anything without thinking of my ex. Not because I miss him, hell no, I just get flashbacks to what happened and I've even had a small panic attacks the times the times my man and I have tried to do anything more than fingering. I don't know what to do. I want to be able to pleasure him, and I want to be pleasured, but I get so scared for no real reason. I need help.