Can't handle the side effects of meds

So I'm from India and I've been taking Attentrol (atomoxetine) which I think is the equivalent of straterra here. I started with 10mg, took it for about a week then switched to 18 mg and I've been taking it for about 2 weeks. I'm aware that this is a low dosage and it takes a while to experience improvements.

However the side effects are brutal. I have constant headaches and feel tired. I just lie down after taking the meds. I'm barely functional. After taking it in the morning I feel miserable until 6 in the evening when it eventually wears out. I don't know if I should continue taking them cause even if my concentration gets better with a higher dosage I'm pretty sure the side effects will also worsen.

I tried stimulants (amphetamine) before this and they sorta helped me for a while but made me anxious and also caused fatigue.

My doc told me I don't have any other options in terms of meds so I should continue taking my current medication and see how it goes.

I just want to be able to concentrate and finish college. I don't know what to do. Could use some advice from you guys.