Some schools don’t count FL taken in HS and want to see 3 - 4 year of the same language in HS. For highly selective colleges, dropping your FL could be an issue. I would worry about taking an accelerated summer program if you struggled during the school year at a slower pace (summer programs move very very quickly). Can you get a tutor for Spanish?
Ask your current teachers or guidance counselor about the course load/rigor. They will also know. At my D’s school, AP euro was as much work as APUSH so I wouldn’t recommend adding that into the mix without having a serious discussion with your history teacher first.
PS. I saw your other post…yes you will need some level of physics before graduation. Doesn’t have to be AP or even honors but some level of physics. If you don’t have room for that in your senior year schedule, I’d consider adding regular physics to your schedule for junior year. I’d prioritize it over AP chem if necessary since you took H chem last year.