It wasn't exactly rape, because I said 'oh, all right' under the pressure.

This is a good example of a grey zone. You did, in fact, consent -- but your consent wasn't freely given, and when all's said and done, what that guy did wasn't right. The remedy for something like that isn't, I think, to try to pursue it as a legal matter (even if we lived in a world that handled rape prosecutions better); what we need are better social sanctions that tell people it isn't okay to do that.