I'd be doubting you'd be doubting she'd be doubting we'd be doubting you'd be doubting they'd be doubting
Perfect
I should've doubted you should've doubted she should've doubted we should've doubted you should've doubted they should've doubted
V-ing perfect
I should've been doubting you should've been doubting she should've been doubting we should've been doubting you should've been doubting they should've been doubting
Negation
Simple form
I shouldn't doubt you shouldn't doubt she shouldn't doubt we shouldn't doubt you shouldn't doubt they shouldn't doubt
V-ing form
I shouldn't be doubting you shouldn't be doubting she shouldn't be doubting we shouldn't be doubting you shouldn't be doubting they shouldn't be doubting
Perfect
I shouldn't have doubted you shouldn't have doubted she shouldn't have doubted we shouldn't have doubted you shouldn't have doubted they shouldn't have doubted
V-ing perfect
I shouldn't have been doubting you shouldn't have been doubting she shouldn't have been doubting we shouldn't have been doubting you shouldn't have been doubting they shouldn't have been doubting
Interrogative form
Simple form
should I doubt? should you doubt? should she doubt? should we doubt? should you doubt? should they doubt?
V-ing form
should I be doubting? should you be doubting? should she be doubting? should we be doubting? should you be doubting? should they be doubting?
Perfect
should I have doubted? should you have doubted? should she have doubted? should we have doubted? should you have doubted? should they have doubted?
V-ing perfect
should I have been doubting? should you have been doubting? should she have been doubting? should we have been doubting? should you have been doubting? should they have been doubting?
Interro-negative form
Simple form
shouldn't I doubt? shouldn't you doubt? shouldn't she doubt? shouldn't we doubt? shouldn't you doubt? shouldn't they doubt?
V-ing form
shouldn't I be doubting? shouldn't you be doubting? shouldn't she be doubting? shouldn't we be doubting? shouldn't you be doubting? shouldn't they be doubting?
Perfect
shouldn't I have doubted? shouldn't you have doubted? shouldn't she have doubted? shouldn't we have doubted? shouldn't you have doubted? shouldn't they have doubted?
V-ing perfect
shouldn't I have been doubting? shouldn't you have been doubting? shouldn't she have been doubting? shouldn't we have been doubting? shouldn't you have been doubting? shouldn't they have been doubting?