Money Management - A Skill I Lack

After all the hassle of getting my refund back into my account last week, what did I go and do yesterday? Spent most of it!
I had to get my sister's wedding gift (I settled for vouchers as they have a long-established home and I don't know what they want or need, so they can decide themselves), as well as this I got them a nice card. I thought, as I had been stressed (over the money issues) I would treat myself. While I was looking for some nice cuff links to wear at the wedding I saw that Prowler had the paperback version of Michael Tolliver Lives which I have been looking for for months, so I got that (and promptly forgot about cuff links). I then thought I would pop into Orbital Comics to get a "couple of comics" to tide me over until payday. I spent £22 in there just getting the "essential" ones! Am I stupid or what? Don't answer that it was rhetorical!!
I still have money, enough to last me, but I still look at my balance and despair! Knowing that I am acting supervisor at work today and tomorrow doesn't really help as all that gets me is an extra £6 per day (before tax), hardly worth being more bored than usual!
Oh well. Only 2 more shifts and then I am off for 3 days for the wedding! I should be looking forward to it, but I am not. I don't want to make a speech in front of a lot of strangers, I will have to decide if I can be bothered to go through the rigmarole of coming out to people at the wedding or not (I don't care who knows, I just hate having to be the one who tells people. In these instances I would rather other people do the telling, it doesn't seem like I'm making a big deal out of it then!).