Does acth causes both aldosterone and cortisol secretion?

Yes: Although acth predominantly controls the secretion of cortisol from the adrenal glands, it also has a minor role in controlling aldosterone. The major control of aldosterone is through the renin/angiotensin system from the kidney, and relates to sodium and potassium balance.

ACTH ALDO Cortisol: I have seen two families in which ACTH is the major driver for aldo production. They have the syndrome called GRA (Glucocorticoid Remedial Aldosteronism) caused by a cross over mutation in the genes controlling aldo production so that the major controller of aldo is ACTH. As you are young and making this question if you also have HTN your team should consider this. Many do not have low K.