What was the 1RM sequence? If your max was 155 the first time, try this next time ( if your plates don't add up to my numbers don't freak out, do 70 or 80 instead of 75 for example ):
Dynamic warmup.
Hip flexor stretches.
2 mins rest
SQUAT:
5@BW
1 min rest
5@45lbs ( bar )
1 min rest
5@75lbs
1 min rest
3@105lbs
2 mins rest
2@135 lbs
3-4 mins rest
1@155 lbs
After that, keep adding 5 lbs with 3-4 mins rest. So 155, 3-4 mins , 160 , 3-4 mins, 165, 3-4 mins etc. When you fail, rest 3-4 mins and retry the failed load. If you fail again, that's it.
Do that a few times, as I said again you can't expect to meet your real max in your first squat session ever. Body and CNS will adapt to the new movement and you will see huge gains every new time. It should take 3-4 tries before we have a 'reliable' max. Oh and do NOT do that every day, leave 48 hrs at least between tests.
PS : I agree with ChrisM and that is a basic principle , you better fail than lift it wrong. Your form must be tight and your depth legit. What weight you squatted does matter, and it matters a lot, but if it was not a legit squat, it does not count, you can't make safe conclusions out of it.