Incorrect dosage of chronic meds dispensed

I received from chronic medication for high blood pressure from clicks cornubia which is collected on a monthly basis . .I have my medication on a 6 months repeat and this is my chronic medication. After receiving the April chronic medication and taking it for a week I became very ill with terrible headache and nausea.I looked at the package of the medication and .realized that the incorrect mg was dispensed to me and this was the result of my terrible headaches.i would like this to investigated throughly as this has endangered my life .I was given a 10mg of blood pressure meds instead of 5mg