As you can see, Newtothevapelyf3, there are as many answers to your questions as there are vapers.
If I'm reading your post correctly, though, you're ingesting one bodacious amount of nicotine, especially for someone who smoked so little and for such a brief period.
7-10 milliliters per day of 2.4 to 3.0 mg./ml. is more than most vapers can take. For instance, I was a
three-pack-per-day smoker for 47 years, and I started with 3 ml. per day of 24 mg./ml. I had to dial that down to 16 mg./ml. within a couple of months: that amount was giving me heart palpitations and headaches, both symptoms of nicotine overdosage.
I suggest you reduce the nicotine concentration.