[trux]

I agree with the above comments about possible over-training and mental/psychological barriers, but since you mention you suffer from allergies, it can definitely have influence too. Personally, in the period of allergy reactions (April - May for me) I have difficulties to keep my epiglottis closed during statics - it simply does not seal properly and once the contractions begin, I am loosing considerable amount of air though the mask, and finish each statics with practically empty lungs. Therefore, I started using Paradisia nose clip and the problem is solved.

However, the effect of allergies may differ, and in serious cases it may be quite important, so do not bother with it too much. The purpose of the training is not breaking a PB each time, and not even coming close to it, but rather improving the technique, relaxation capabilities, increasing the tolerance to contraction, hypercapnia, and hypoxia, improving diving response, and working on physiological adaptation. The harder the conditions, the better. The reached times are absolutely secondary and unimportant.