Thank you for posting your query at DoctorSpring.com
Thank you for being so comprehensive. Even tiny details can be very important.
I have gone through your entire query, and i can assure you there is no reason to worry. He can't transmit any STD to you by inserting his finger, even though such an act can be dangerous considering you are already a piles patient. So be very careful and especially inform your partner not to do that ever again. This may lead to excessive bleeding, which will then make your anal area prone to infections.
From your entire act, he gave you oral sex, and the only STD that can be transmiited is HSV. If he didn't have any open lesion, then there are negligible chances, however unprotected oral sex can lead on to herpes infection. A lot of people won't even know they have herpes since the symptoms can be extremely insignificant. Apart from that you have no other risk. Definitely not HIV. I would have been worried if you both had unprotected intercourse, more so if it was anal intercourse. I will advise you to abstain from unprotected intercourse, since you already can see you go Mycoplasma from him.
Do let me know if you have further queries,