Since then, I cannot sleep well, because first I think that my hand could have
touched the external part
of the condom before I masturbate myself, thus touching my penis. Secondly I am afraid that she could have passed hiv to me as she put her mouth on my genital.
The other concern is that, even using condom (I am always careful when removing the air of the tip, unroll until the end, etc), I am very concerned that something could have happened.