Is it major shirk to do an act of worship solely to gain the praise of people, or is this still minor shirk? I mean if someone prays without intending Allah at all, but rather only does it to gain praise from people. Also, is it shirk to recite quietly in loud prayers due to shyness?

Ustadh AbdulAziz al-Haqqan
I advise you to seek medical help if you suffer from OCD thoughts (waswas).