Unfortunately, the only way you can tell is by trusting what your injector says. Rely on your instinct. If you feel that something is amiss, I suggest you visit another injector. That's why it's important to have a thorough consultation before your treatment.
Dilutions are not the concern but rather the number of units used. The amount of Botox used and the placement depends on the individual's movement and strength of the muscles. 50 units may be the correct amount for you. You should have treatment with an experienced dermatologist or plastic surgeon that you trust. He/she would only want you to have the best possible result.
Did I get all the Botox I paid for?
You rely on the integrity of the physician that you see. Most doctors will inject you with exactly what they say.
Some will cut corners and if your sense is that you are dealing with someone that is not doing what they say, ask about the dilution. Botox comes in a bottle of 100 units, Dysport in 300 units.
Different doctors reconstitute with different amounts of saline. The dilution does not really matter but the amount of units injected does. I tend to inject with about 25 units per site and I charge based on this.
From the dose you describe, this seems like you did not get enough for three areas.
Botox. It's all about the units.
We reconstitute Botox differently for different uses. I wet it down more for arm pits, less for eyes. You are right, it's units that count. But there has to be trust between you and your provider. If there isn't, how can you let them put a needle to your flesh? Short of them buying the 50 unit vial (half size) and using it all up in front of you and giving you the empty, I don't know that there is any way to "prove" how many units we used. If you need that much assurance, maybe you need to develop some better communication and trust with your provider. Also, onset of action of any drug, Botox included, is variable. Sometimes one day, sometimes five. It has no relationship to the units used.
Different dilution rates can still yield similar results
The only way to know for sure how many units of Botox are injected is to ask your provider. You should be able to trust him or her. If you don't trust him, you should go elsewhere, but there are several explanations that might account for the variances you're noticing.
The Botox comes to us as a freeze-dried powder in a glass vial. Each injector reconstitutes the powder with a saline solution. They can put in 1, 2, 2.5 or even 4 ccs of fluid. The more saline, the more dilute it will be and the more fluid will need to be injected to achieve the desired effect. One way is not better than another - they are just different and each injector will have his/her preferred method.
If your previous results appeared in 24 hours, this may have been a more concentrated solution (less saline per unit of botox). It is normal for botox to take 3-7 days or more to see the full effects.
Botox can be diluted in many concentrations. Its effect is always the same when injected by an appropriately trained individual in how to dilute and how to inject the material. The important thing is how many units where injected and where. This is why it is important to have an appropriate individual that you trust to perform a medical procedure on you, do the procedure.
Usually, it takes 3 - 7 days to see the results with Botox. Depending on the dose, it should last 3 - 6 months. I like to use a more concentrates number of units per area and my patients ususally come back an average of 5.5 months later.
Botox injections usually take 5-7 days to "work." Every injector uses a different technique. Some doctors use more concentrated Botox than others, so the amount of injection will be different.