The short answer is no you are not allowed not to fast.
Most scholars (Maliki, Shafi'i, Hanbali, see also this fatwa) say that one should do the niyyah (for Ramadan fasting) during the night (before fajr), but in cases like yours, you have missed the time to make the niyyah you are asked to do it once you wake up this is a correct qiyas to the similar case of the person who missed prayers -because he/she was sleeping- and has to perform them once he/she remembers them. So this is an allowed exception for the "rule".
On the other hand note that:
قال شيخ الإسلام كما في الاختيارات: ومن خطر بقلبه أنه صائم غداً فقد نوى
Ibn Taymiyyah said: If you had in mind that you are fasting tommorrow then you already have made your niyyah.
So the niyyah matter is easy.
Note this rule -of making niyyah at night- applies for Ramadan fasting kafara fasting and for those who have to fast missed days of Ramadan. For optional fasts most scholars say performing niyyah before fajr isn't necessary you could even wake up in the day in decide to fast, as the Messenger of Allah (Peace be upon him) used to do.
But if you made suhoor a condition for fasting (and it was not an obligatory fasting) than you could still not fast.
If you didn't fast intentionally because you didn't make niyyah and suhoor in an obligatory fast like Ramadan, then you may have to do a kafara feeding 60 poor people or fasting two successive lunar months. Because you committed a sin.
You are only allowed not to complete (an obligatory) fasting once you feel that fasting this day would make you suffer or would harm you in that case you only need to make up this day without any kafara as stated for the sick in (2:184). For example if you felt terribly hungry and/or thirsty and felt you couldn't complete your day fasting. As Allah says:
... and do not throw [yourselves] with your [own] hands into destruction...(2:195)
... And do not kill yourselves [or one another]. Indeed, Allah is to you ever Merciful. (4:29)
Here some references in Arabic:
About the niyyah.
Fasting if you missed iftar and suhoor.
If you can read Arabic I also strongly suggest you to read the answers on the questions 39, 45 and 47 on this site.
See also this Fatwa on the niyyah in English.