Welcome to our Forum. I'll go straight to your questions. By way of preview however, since you and your ex were tested and negative for common STDs, I see no reason whatsoever for additional testing as the relationship ends.
In answer to your specific questions:
1. See above. I see no reason for testing. You both tested negative for the major STDs and their consequences.
2. No, there is no appreciable risk for HIV, hepatitis, or other blood borne diseases from this sort of scrape. If there were, there would be an epidemic of pediatric HIV, wouldn’t there. The HIV virus would not survive outside of the body long enough to cause infection.
3. No penetration, no risk for nearly all STDs.
Finally, because you mention HPV several times, I will add an additional contact. Having had 5 prior partners, virgins or otherwise, you can be quite confident that you have had HPV. Virtually everyone has. Over 85% of sexually active women will have HPV infection at some time in their lives. The figure for men is less well studied but similar. In some HPV will cause genital warts, in others it will not cause warts but may lead to changes in PAP smears. In nearly everyone who gets HPV, warts or otherwise, the infections will resolve by themselves without therapy in 8-24 months. In a very small minority of women, HPV infection can persist and lead to the pre-cancerous lesions that PAP smears detect and which can then be treated. For men there is far less risk of any sort.
To emphasize this point, I am including a link to an earlier detailed response that my friend and colleague, Dr. Handsfield made to a similar question.
http://www.medhelp.org/posts/STDs/HPV-Transmission/show/1522088
I hope these comments are helpful. I would not be worried. EWH