Where to go and what to do?

I'm an 18 year old female currently studying in Birmingham. I am currently going for 1st dan in judo and I am looking at starting a new martial art, I am not entirely sure what to pick up. I don't want anywhere that is too expensive, as a student I am pretty poor. I was thinking maybe BJJ or MMA, I am not really too fussed what, I just want something enjoyable that is relatively cheap. So what martial art and clubs in Birmingham would you reccomend