I know headbanging is a common issue with toddlers but all the references I can find seem to be about headbanging as part of a tantrum type behaviour, and I think this is different. My DS is nearly 14 months and recently he has started to bang his head on purpose - he will either pick up something like a toy and bash it on the side of his head or he has just started bashing the side of his head against our coffee table (which is glass/metal) - then he cries a little bit like it has hurt (whereas when he was hitting himself with a toy he didn't seem hurt by it at all) - why do you think he is doing this? At first I think he just thought it was funny because we laughed at him doing it the first few times, and he is very into copying things at the moment or doing things which he knows get a reaction (laughing etc) but I tried to ignore it because I didn't want to encourage him to do it any harder.
Do you think he's doing it because he knows if he hurts himself he gets a cuddle? Ever since he has been crawling confidently I have always put my arms out stretched wide to say "come here for a cuddle" if he hurt himself minorly and was crying (Obviously if he was really hurt/distressed I went over to pick him up) and he usually perks up as he crawls over but obviously gets a cuddle anyway. We cuddle and kiss a lot so I don't see why he would feel the need to headbang to achieve this though. It doesn't seem to be when he is frustrated, it happens at random times.