That’s a great question, @Babywitchbxtch, and I can see you’ve already got some great answers!
There was a similar question asked a while back and @MeganB wrote a fantastic response. I can’t say it any better than she did, so I’ll add a link to it here for you:
Everyone has their own limits and routines- I’d say go ahead and cast the first spell and then see how you feel. If the second spell is related to or similar to the first, then they very well might complement each other.
However, if the additional spells are for completely different intentions, I imagine it would be hard and draining to continuously change and direct your focus. Pretty exhausting spellwork! It never hurts to take a break in between and come back later, refreshed 
Blessed be! 