Brief Answer:
Review Ultrasound / MRI for disc / thorough Clinical examination

Detailed Answer:
Hi.
Thanks for your query.

To recapitulate:
male / 41 - CT scan for pain in abdomen a few months ago - for pain in abdomen - was called by the Doctor to say everything was fine - online result last week - enlarged spleen and herniated disc - ? worried ?? about spleen ... Going to Doctor on Friday.

I would be happy to get the following:
Detailed history about your pain in abdomen, the past problems and present situation ?
CT scan report; you can post as > YYYY@YYYY
Size of the spleen ?
These points may help me more to a better opinion.

As a general discussion my thoughts are:
Enlarged spleen usually does not cause pain in abdomen unless there is some lesion that develop in it like an abscess. Mild enlargement without obvious correlation with the symptoms and signs might have made your Doctor not to bother about it.
Herniated disc : Again the most important point is: MRI is the best diagnostic tool to decide about whether the disc is causing symptoms / is it pressing on the spinal cord and / or nerve roots ? Whether its presence is correlated with the symptoms of pain in abdomen or any other symptoms or not ?

I would suggest you the following:
Anyways, you are visiting a Doctor. you can discuss about this in detail and you can have a review ultrasonography to decide whether the spleen is still enlarged or normal. If enlarged, whether this is just above the normal measurements (borderline) mild / moderate / massive ?
You have then to undergo the tests of the blood and others as may be suggested by your Doctor after a clinical examination or a reference to the Hematologist.

I hope this answer helps you to get rid of the concerns either by having a normal spleen at the clinical examination / ultrasonography and if enlarged, then to undergo relevant further investigations and management.

Please feel free to ask for relevant further queries or if you feel that there is a gap-of-communication.

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