Welcome to HCM.
Blood, if it is from a HIV individual, may be infectious till it gets dried completely throughout its core. Outside body it cannot withstand drying. But touching with bare hand and putting the finger in the mouth and all very rare possibility unless you are having some injury
or abrasion on your finger or mouth. If there is nothing like that there is no chance. Even in case of injury on your finger the possibility is very remote. So don't worry.
Get it cleared with a rapid HIV test
after 3 months.
Nothing to worry. Have a nice day.