Not buying Bitcoin, am I being dumb

I’ve been saving up my money for the past month, I’m currently on £6000 in my bank and £5000 in Ethereum, I’ve been trying to save my bank money until I can get to like 16k and buy a whole bitcoin with a couple thousand left in my bank. My job is self employed and I’m also a live at home student so I don’t really have expenses, but my income is inconsistent, I’ve earned £4000+ one week and then £50 the next week. I get more student maintanence loan money january too (£1500)

Anyway, should I just save up and then buy when I hit the 1bitcoin mark or start pouring some in rn? It’s at its all time low basically for the past year or two but then again the economy is doing bad rn so I could see it going lower.

What would you suggest, I appreciate any help and if I have left out any gaps please ask in the comments