Your pH is probably too high, so YES, a pH meter would help. It is difficult to give good advice if you don't know what the pH is, but it probably isn't a loss yet. Let it sit at room temp (warmer if you can) and test for stretch every hour or so. Like Mozzarella , the pH needs to hit 5.3-5.4 before it will stretch. Without a pH meter, that's what you do - wait, test, wait, test.....