Job offer rescinded after negotiation?

So this was my first professional job I had properly gone for after just graduating university with a 2:1 . I had actually been reached out to by the recruiter for this job as she really liked my CV,I was really delighted about the job and thought I would be a great fit for it. It was a procurement admin at £24k 9-5:30. I went to the interview and the feedback was super positive, they were blown away by my interview, said I was really engaged with the interview and my answers and questions were all really brilliant. I was also told after all the interviews, they believed I was the best and strongest candidate by far.

I got the call today saying they would love to offer me the role at the initial offer of £24,000. I would be happy to have taken this but my family member who is also in a high level position within the procurement sector said that I should always try to negotiate a little over , as the worst they could do is just say no and reoffer the original salary, and asked if they would be willing to negotiate to 26k. I thought this was a relatively small increase of 8% seeing as I was a university graduate which they wanted and I also have 4 years of full time customer service experience which they also wanted. I know I didn’t have experience in the field to leverage however I thought with my degree etc, 2,000 wasn’t too much to ask.

They got back to me via the recruiter to say that £24,000 was the most they’d be willing to give and I was happy with that. I just had another question to ask regarding the role and the recruiter went back to ask. I didn’t get a quick call back so I called back and she told me that the manager had starting having doubts regarding me and believed I would not be happy with the salary and therefore may try to find a higher paying job quickly. This was absolutely not the case however I was told that the offer had now been completely rescinded, without me being able to even have time to accept the original offer.

Was it me who made the fault or did I dodge a bullet?