Imam Ahmad (rh) was asked if one could cry when on a full stomach and he replied he doesn’t think that’s possible. So try not to overeat so one can shed tears easily for Allah.
A scholar of the past saw a man crying in Salaah and he said, this man will be asked what he intended with his crying. A person should do as many good deeds in secret as possible especially things like crying otherwise who are they doing it for?
A scholar of the past mentioned that a person who sheds floods of tears in du’a in witr yet he struggles during the actual tarawih isn’t a good sign.