Morning
@spence.
Blurred vision can last a while. This is due to our lens changing shape because the refractive index of sugary tears (with high levels, our body tries to get rid of the excess sugar through any means possible) is different to that of salty tears. It is not uncommon to buy a pair of ready readers to tide you over. This can last about a month. As all thing diabetes related, we are all different. Some people have blurred vision for a few days, some a month, some longer.
Belly ache is less common. You say the timing is random. Have you noticed the ache is worse when your levels are higher? I ask because it is a symptom of high ketones which come with high levels. It may be useful to check your levels when you have your belly ache. It may be unrelated to diabetes which you can tell based on your levels. It may be related to anxiety over your diabetes.
No need to apologise for the questions, it is what the forum is for.