Easy? Loading Screen LINK Help

So, in my loading screen link at the end I have:
?steamid=%s?mapname=%m

I can only use one of those… Like:
?steamid=%s

Otherwise it will literally display this on the loading screen:
(SteamID)?mapname=%m

Please help me fix this dumb issue… I think this is stupidity on my part.

what loading screen do you have? or did you make it yourself?

you only use one ?, you use & for the rest
(like **?t=1480821&p=48443032&**viewfull=1#post48443032)

Thank you for that PortalGod.