Yes, the whole pH thing is confusing, and rightly so! It's mostly bunk!!! LOL!
First of all, you cannot tell anything from just one pH strip test. The mouth and urine change throughout the entire day. For a good understanding of what's going on with your acid levels, you ahve to take tests at least 3x daily for at least a week and average it.
One thing you CAN do with the strip that is very powerful is take a measurement right before you eat a meal that you cooked. The anticipation of food should start the alkaline enzymes flooding into your system and create a very purple strip. If your mouth still reads acid at that point, then you know that your digestive fire is incredibly weak and you should fast and take digestive enzymes with every meal.
Another good learning thing to do is to take a reading when you're stressed and/or angry. We get so acidic at that point it's amazing! it shows quite clearly how damaging such emotions are and how meditation is healing/balancing.
So what you want to focus on rather than the whole pH thing is nourishment and power of digestion. Are you eating nourishing foods and are they getting digested and absorbed? If they're not, where in the process is it getting broken down? Perhaps you're not chewing enough, eating too much at once, have too little stomach acid, too few enzymes. Papain is an enzyme, it does nothing to increase stomach acid. It simply helps the small intestine break down and absorb proteins.
Are you contributing to your bank accounts of nutrients, or are you making huge withdrawals? Whole foods make deposits, refined flours, sugar, microwave lunches etc. tend to make withdrawals.
Make up a symptoms list and let your symptoms be your guide. If you feel great then no matter what any "expert" says you must be doing something right! :)
For info about how digestion works, join the Yahoo nutrition class. We go over digestion in one of the lessons. There are still only about 11 lessons so it's not a difficult online class to get caught up on. :)