It appears to be genuine, but I have my suspicions (about it).

这看来好像是真的，不过我(对此)有怀疑。

youdao

For some months past I have struggled with doubts and suspicions which have embittered my life.

我已经同我的疑惑和怀疑搏斗好几个月了，这种怀疑弄得我的生活痛苦不堪。

youdao

I must admit, over the time you've been here, certain... suspicions have begun to gather in my mind. I'm going to be frank here... are you a doctor?

我必须承认，你来过这以后，某些……疑问已经在我脑海中产生，老实说吧，你是博士么？

youdao

I'll never know 100 per cent whether it was a detective, but I have my suspicions.

BBC: India's 'wedding detectives' enjoy booming trade

" When asked where the story may have originated, he said, "I've got my suspicions.

CNN: Bush acknowledges 1976 DUI charge