Hello,

See, every year there are innumerous students who appear for NEET, qualify the exam, and not everybody gets an opportunity to secure a GMC seat since the competition is extremely high, now one of the prominent factor to go or not go for private colleges is affordability since the fee is on higher side, also what comes into consideration while selecting is infrastructure, faculty, patient flow etc, hence you need to research all these areas well prior to taking any decision,

next whether repeating NEET or changing stream depends in which domain your interest lies, there have been many candidates who have repeated NEET and in some cases it works well or in other cases it may not work well, this to a large extent also depends how well and efficient you utilize your time of one year to secure GMC seat when the competition is so intense, the decision to repeat NEET depends on how much dedicated you're to only make a career in the domain of medical science, if you feel this is your calling, and you can make the most of the one year, then go  ahead, else if you feel there are other choices which you find yourself more suited then there is no need to repeat NEET, all these answers lie within yourself, since you're are the best judge regarding this.