I need to report my rape

4 years ago i was the victim of 2 separate rape accounts. I never reported it. I feel the need to do so now but I don’t know how to do it. Do I call 999? Do I call 101? Please can someone tell me what to do. I suffer with really bad anxiety and depression (not a result of what happened) and recently it has been causing me to have many, many severe panic attacks. I need to report it and get it sorted because I can’t keep going on as if nothing happened because it did. I’ve finally realised that and I’m ready to come forward. I just need to know how