Buy a Nexus 5 or wait?

The Nexus 5 costs €400 euros over here, which is about $550, for the 16gb model. This week, the Nexus 5 will be €330 ($450), just for a couple of days.

I'm having the HTC One V now (don't leave out the 'V'!), it's got a 1ghz single-core processor (don't ask why I got this one last year, very very bad decision!). Next to my One V, I have the 2012 edition of Nexus 7, which I use for playing games (GTA, heavy 3D games) and reading some tasks. My One V is now coming in to a stage that it freezes when I read news via Feedly! Stupid thing.

The Nexus 7 is going to retire soon (not my choice! Things are getting older by the time.) and I was looking for a replacement for both my tablet and phone to buy this fall, so I was looking for a phablet in the direction of the Note 3. I can't afford the Note 3 at the moment, but it may be affordable by the end of the year (I hope so), then I saw the tax free promotion and now I'm stuck.

I can wait and hope that the Nexus 5 or the Note 3 will be in my price range in the coming months (max. is absolutely €330, but less is better,). The Nexus 5 is currently €350,-, second-hand, so it's a great deal.

€330,- is a huge amount of money for me, as being a teenager, maybe good to mention..

I'm currently learning to advance in Android application development. I currently advance PHP, MySQL, JS, HTML, etc. very well, but yeah, that's not Java so I need to learn things from the 20% base I got from PHP.. (most people say that PHP is very similar to Java, but I notice the differences.) My plan is actually to earn money with developing apps but it's kinda hard because school takes out a lot of spare time! So, no, not all teenagers are buying great devices to show them only to their friends and say they have such a expensive phone!

I just need to get some advice, it's hard for me and maybe you can help me with some tips or suggestions and please criticize me about my English, because I want to make progress in the language. So, should I buy the Nexus 5 or should I wait until this fall and look further.