Your quant has been pretty consistent, so I think we can assume that you'd likely get a 50 or 51 if you took the real test right now.
Verbal, though, has fluctuated a lot more. Here, you have to assume that you're likely to score at the lower end of the range - because until you know why your score is fluctuating, you can't take steps to try to minimize the fluctuation and keep your score at the top end of the range.
So why do you think your score is fluctuating so much? I can think of two reasons why you'd have a lot of questions wrong at the end of the section:
(1) timing problems (rushing, having to guess, therefore making careless mistakes or just having to guess blindly)
(2) mental stamina problems (getting mentally fatigued and missing questions that you can ordinarily answer correctly)
Of course, both could be happening. It sounds like you definitely did have timing problems (you mentioned time pressure). Do you think you were also suffering from some mental fatigue?
(Here's how to tell what it feels like:
http://www.manhattangmat.com/blog/index ... you-crazy/)
On the questions where you were rushing: were you forced to (because you were running out of time)? Then you have timing problems. Did you rush even though you weren't forced to? Then it's more likely a mental stamina problem - sometimes we start rushing when we're tired, even though we don't have to. Depending on what the culprit is, there are different ways to address the issue.
Next, why specifically did you miss those questions? Did you just get very unlucky and happen to get a string of questions that were too hard for you, no matter how much time you would have spent? Or did you make some careless mistakes? How many were careless mistakes? What were the actual mistakes themselves?
Finally, when deciding whether to go in and take the test in general, ask yourself this: if you scored what you just scored on the last practice test, would you be happy with that? Or would you be significantly disappointed and definitely take the test again? If the latter, then you probably shouldn't take the test right now.