I had the same issue. I overcame it using a simple method. More often than not, we know that the question we face is difficult. So, rather than giving a lot of time for a question that we may not get right, i prefer giving it a guess and face the next one. Also, i have a chart with queston number and time remaining, that helps me.
I used to write this table right after IR in the worksheet and follow it during the quants test. I practice to write this chart in the break and i want to follow the same on the Official GMAT exam day too. This chart helps me to have an eye on whether i'm lagging behind in time or not. This gives a some buffer time too, so even if im slightly behind, i'm not lagging. But, if i strictly follow this, i have all the time in the world to tackle all the questions and complete it on time.
Quants:
Q Minutes Remaining
======================
1 75
6 65
11 55
16 45
21 35
26 25
31 15
36 05
I also prepare another chart in the Quants/Verbal break for verbal section.
Q Minutes Remaining
======================
1 75
4 70
7 65
10 60
13 55
17 50
20 45
23 40
26 35
29 30
32 25
35 20
38 15