First cycle = too much panic about gyno.
If your nipples start itching and hurt when you touch them (like sticking needles), you should start taking an AI or increase the dosage asap.
When I'm on cycle I do the following for testing on gyno:
stand up right and hold your one arm completely stretched upwards. Your pec will now become stretched and with your other hand you can check your nipple area more easily for lumps.
If you focus too much on tingles you'll start imagining things.
When your AI is legit and you get the dosage right, you'll be fine.