ANSWER:

You should not make dua after salah, this is the time to make the prescribed dhikr. You should make dua in your Salah, in sujood and in the Last tashahud, before making salam, even in your own language if you don’t know how to make it in Arabic. You should not say ameen to your own duas. 

Making dua before sleeping doesn’t come under innovation.

Sheikh I have made it a habit of makin Dua after every salah and when I go to sleep aside from the dua’s for sleeping. Ex. I ask Allah to help me wake up for fajr n forgive me for the sins I committed during the day. It helps me remember allah, it it bid’ah? Also when we are in sujood and we make a Dua do we say amen or just make the Dua?