He showed me his tests and his is healthy - should I be concerned still?

[paradis]

Hi all!
I want to start having bare sex (me bottom) with this wonderful guy I met and really like and just wanted to hear your advice.
I am healthy, tested, no STD.
He has shown me his test results and is neg and STD free. The test was done last week.
We already did unprotected oral, kissing, but then protected intercourse.
What concerns should I have if I want him to go unprotected inside me and also finish off inside me?
Is there an "incubation period" etc. He does assure me he is safe, gets tested at least once a year and plus I saw the test results from a clinic I know.
Thank you all!