Brief Answer:
Your symptoms might be due to variation in the blood pressure, which is noted with this combination

Detailed Answer:
Hi
Welcome.
I have gone through your query.
When this agents are given together, in some individuals it may cause confusion, hallucination, seizure, changes in blood pressure, increased heart rate, fever, excessive sweating, shivering or shaking, blurred vision, muscle spasm or stiffness, tremor, incoordination, stomach cramp, nausea, vomiting, and diarrhea.
As you are experiencing lightheadedness and as well as fullness, it may be due to variation in the blood pressure.

I would suggest you to monitor your blood pressure at regular and discuss with your consultant about the symptoms that you are experiencing. And also watch for the other symptoms that I have mentioned above.

Hope this helps
Take care

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