There is a possibility that you caught a non-STD. If you are kissing, etc. You can exchange any bacteria, virus, or fungus that you may currently carry. An example would be Adenovirus which is the most common cause of viral sore throats and can also cause pink eye. Your immune system probably took care of it by now (if thats what it was).
It is possible to catch HSV1 from kissing. (It can cause sore-throats during its initial infection). However, this is not something that you should worry about. 60% of the US population and upwards of 80% of the world's population has it. It causes cold sores on your lips.
Swollen tonsils and pink eye seems more likey to have been a viral infection and coincidental in timing to your unprotected sex,STD's such as Gonorrhea,Chlamydia,Herpes and the like usually although not always carry symptoms such as abdominal pain,discharge,itching,rash and pain when urinating but because not everyone gets these symptoms it would be wise to be tested for everything at your GUM/STD Clinic .....
All unprotected sex whereby you do not know for sure the status of the person carries risk of contracting an STD ...... the fact that the woman was older has no bearing on anything.
Get checked and "play safe" in future!!
Daisy