what would be the chances of my female being pregnant?

my female dog was tied with a male dog about 28 days ago they where tied for about half an hour what are the chances of her being pregnant and would there be any signs right now and if not when would i see signs she is very clingy and go wherever i go even to bed she has gone off of her food but she will eat our food no problem so can someone help me with this

Go to the vet. If she IS pregnant, then she has a little under 35 days to go. It may not be too late to have an emergency ovariohysterectomy done.

At 28 days your vet has a window of about 5 days that he will be able to feel the abdomen to determine pregnancy. After that an ultrasound or x-ray (done late in pregnancy) will be needed. It's always a good idea to get a vet involved early to answer any questions you may have and be on call in case of an emergency. At 4 weeks you should notice her waistline disappearing, but the real weight gain doesn't begin showing until 6 or 7 weeks and maybe more with a large dog carrying a small litter. Her stomach would also be firm. Her teats firm and slightly more pronounced.The odds of her being pregnant are high. The clinginess is a sign. I would be very careful in not feeding her a balanced commercial food preparation. Pregnant dogs know they need extra nutrition and will eat what you supply for them. Put her on a high quality puppy food (no corn, no soy, no wheat, no by-products and a named meat in meal form as the first ingredient). It is normal to have a short period of lack of appetite and maybe even some morning sickness at about 2 weeks, but shouldn't be the case at 4 weeks. Maybe you spoiled her with table scraps when she went off food during that time?