Are actions that help invoke mindfulness of God and increase humility, but at the same time greatly arouse lust and expose one to falling into immoral acts, considered shyness or satanic whispering? And should one continue with them or desist from them, and how?

What you mentioned about accustoming yourself to shyness before Allah is a good habit dictated by sound human nature, and among the fruits of this shyness is the consciousness of Allah and the feeling of His accompaniment in all circumstances. As for what you noticed regarding the arousal of desire, we do not comprehend a connection between that and this great character. The link between them is merely a whisper (waswas) and a deception from Satan. Repel the arousal of desire by marriage if possible, otherwise by fasting and avoiding stimulants.