The kit is definitely worth it. It will test chlorine levels up to 50 I think whereas the cheap kit from Walmart will only test levels up to 5. It will also test for CYA. Most cheap kits do not. Test strips are unreliable and inaccurate.

If you truly have no pH reading because it is so low, then you are most likely damaging your pool and possibly equipment. Readings below 7.0 are acidic. You must get your pH above 7.0 ASAP.

At the very least for today, go to Walmart and pick up a cheap OTO/Phenol Red kit (yellow and red drops.) It will not replace having a good kit, but at least with it, you can get a pH reading which you desperately need ASAP.