I would probably recommend you do the Masters, if only because I think it would increase your confidence in your own abilities before moving on to a PhD.

I got a low 2:1, but have sucessfully submitted. I got a few months experience in a lab beforehand which helped secure a place in my department. I found changing onto my own project made little difference to how I felt about the lab work.
I changed my mind about research part way through the PhD, but stuck with it to the end.

You don't need a masters. With a Bsc youregister as MPhil and upgrade iafter the 1st year is completed, sometimes with a mini-viva/report. You have the option to write up as an MPhil and not do the PhD at this point. With an MSc you may be automatically registered as PhD as you have existing experience. I personally think the masters might drag it out and is not needed, but you would hit the ground running and be better prepare as it can take time to work out what is needed. I know someone who did a masters and did still drop out in the first year as it was not right for her. I know someone with a 1st who did one and got a distinction on her masters, and now has a PhD.

You don't need a masters. With a Bsc youregister as MPhil and upgrade iafter the 1st year is completed, sometimes with a mini-viva/report. You have the option to write up as an MPhil and not do the PhD at this point. With an MSc you may be automatically registered as PhD as you have existing experience. I personally think the masters might drag it out and is not needed, but you would hit the ground running and be better prepare as it can take time to work out what is needed. I know someone who did a masters and did still drop out in the first year as it was not right for her. I know someone with a 1st who did one and got a distinction on her masters, and now has a PhD.

What I can suggest from my own experience may sound twee but may give you perspective. The fact you have some work experience already is certainly in your favour; coupled with your degree grade, your eligibility is unquestionable. What I could suggest is this: you seem to discount your inherent academic ability. If you doubt it to such a degree, do the MSc first-it will bolster your confidence (by proving you can do it) and not impinge too much on your bank balance. Then go do your PhD.

no no no you should not go for a phd.
but just in case you do
sign up for phdcomics.com
they pass the time really well