Few things first; if you're a Super Recruiter, your friend activated the SIM on an existing account that previously had an active SIM on it, or the SIM they used wasn't attached to your account, then you won't receive anything,.
If however none of these are you, then when was the SIM activated? There is a window of upto 72 hours from when the SIM is activated for you to receive the bonus, so perhaps you're still within that time frame?
With regards to the £5; you won't be able to receive this until June as it's known as Payback. Assuming the activation in question here took place this month, then the £5 (or rather 500 points) will be visible in your Points tally next month.
You can read more on Payback, how it works, and options on how to claim it here:https://community.giffgaff.com/t5/Using-giffgaff/Guide-to-Payback-points/ta-p/3521553