You would have to do a Lookup or LookupRows to a data extension where that email ID and send time is stored. Possibly a SendLog if had that set up.
Alternatively, you can also set up an automation to query the _Sent data view to write to a data extension so that you can retrieve using the above lookup methods.
GetSendTime and Now(1) only applies to the ...
You won't be able to achieve this with the Update Contact block in Journey Builder.
If you want to immediately update the count, the best course of action for you is to include ampscript for this purpose in all of your emails which would read the current count for the customer and increment it. By doing this the count would be updated as the email is ...
I think I found a solution for this, haven't worked with this for a while, but try the following:
You can make Update Contact Event log a custom ID by pulling dynamic fields from the entry Event.
Make your custom Id the primary key for your log DE.
To find out the entry source id:
go to Dev tools in your browser:
rightclick the Entry Source, inspect. ...
See Salesforce's documentation on this.
If you're updating AMPscript, the documentation states that you need to pause and republish its associated triggered send via Interactions > Triggered Sends > Journey Builder Sends. Once you've updated your email, do the following:
Navigate to Interactions > Triggered Emails > Journey Builder Sends, to ...
Given what you've described, it would be worth looking at this guide to claiming coupon codes by the excellent Adam Spriggs: https://sprignaturemoves.com/coupon-claiming-in-ampscript/
This utilises the ClaimRow function in AMPscript.
You'll need a data extension where the field for your coupon/discount code is the primary key (you presumably already have ...